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No, if anything, it bolstered the arguments against slavery and in favor of equality that were being made at the time.

Anti-slavery and pro-slavery arguments had a long history in the United States before the Declaration of Independence. One of the earliest arguments was the 1700-01 "selling of Joseph". In 1700, Samuel Sewall, a judge in Massachusetts, criticized slavery, having witnessed or become aware of the selling of a person named Joseph by a slaveholder named John Saffin. Sewall rebuked Saffin privately, and then publicly by publishing the anti-slavery tract The Selling of Joseph in 1700.

As Mason Lowance writes in Against Slavery: An Abolitionist Reader, Sewall's tract "reveals a writer who was familiar with contemporary race theory"; the tract has Lowance repeating some common justifications for slavery at the time. After repeating them, Sewall then argues against these justifications. The justifications that Sewell relates and then refutes can be summarized as:

1. The Bible says black people are inferior and have consequently been condemned to be enslaved by others as their natural state;

2. Slavery is justifiable because Africa is a pagan place, and the captured people are being Christianized;

3. Slavery is justifiable because the people being enslaved are prisoners of war (to which Sewall says this isn't actually true);

4. The Bible sanctions generational slavery, period.

While his view is quite a bit segregationist, and it does insinuate some degree of white superiority, Sewall says that black people are just as much of people as white people in the eyes of God, and therefore "[t]hey ought to be treated with a Respect agreeable". He calls "man-stealing as an atrocious crime".

John Saffin, the man who had sold Joseph, responded in his own tract the following year, called A Brief and Candid Answer to The Selling of Joseph. Saffin rejected all four arguments Sewall makes against slavery, instead supporting the common justifications of the time, which included racial inferiority. He then included a poem full of accusations of black people being inferior, essentially saying they have an "innate" nature as cruel, untrustworthy, law-breaking, rape-y sinners:

"Cowardly and cruel are those Blacks Innate,

"Prone to Revenge, Imp of inveterate hate.

"He that exasperates them, soon espies

"Mischief and murder in their very eyes.

"Libidinous, Deceitful, False and Rude,

"The Spume Issue of the Ingratitude.

"The Premeses consider’d, all may tell,

"How near good Joseph they are parallel ..."

These kinds of pro-slavery tracts and accusations would appear occasionally throughout the colonial period, as would anti-slavery tracts, which may or may not talk about equality (though many certainly admonished slavery while at the same time still embracing white supremacy). As Larry E. Tise writes in Proslavery: A History of the Defense of Slavery in America, 1701-1840, the anti-slavery works really began to be published in earnest in the lead-up to the Revolutionary War and the signing of the Declaration of Independence, as natural rights and human rights about liberty and (white) equality circulated throughout the British American colonies. This was matched by the seeds of a cohesive pro-slavery movement:

"As antislavery thought and Revolutionary ideology coalesced in the immediate years before the signing of the Declaration of Independence, so did proslavery. Between 1772 and 1775 five major defenses of slavery appeared under the signatures of American colonials, all of them bent on turning back the tide of emancipation and natural rights. Taken together with the writings they were intended to answer, they mark the arrival of the first phase of an intense trans-Atlantic debate on slavery that continued in cyclical intervals until the second half of the nineteenth century. Although proslavery ideas in the era of the American Revolution were overshadowed by the rhetoric of liberty and emancipation and their expression was miniscule compared to the massive outpouring of proslavery literature in the nineteenth century, the outlines of a distinctive prosalvery critique were clearly present."

As Tise writes in that passage, the pro-slavery rhetoric really didn't take off in writing until after the Revolutionary War. A commonly-used criticism against slavery in the post-Revolutionary antebellum period was that it very much went against the American principle of "all men are created equal" memorialized in the Declaration of Independence.

One of the more famous criticisms of slavery on this basis was the one espoused by Englishman and critic of the American Revolution, Samuel Johnson, though this one was published the year before the Declaration of Independence, in 1775's Taxation No Tyranny:

"How is it that we hear the loudest yelps for liberty among the drivers of negroes?"

More relevant is the quote published in the 1791 biography The Life of Samuel Johnson by James Boswell, who quotes Johnson:

"It must be agreed that in most ages many countries have had part of their inhabitants in a state of slavery; yet it may be doubted whether slavery can ever be supposed the natural condition of man. It is impossible not to conceive that men in their original state were equal; and very difficult to imagine how one would be subjected to another but by violent compulsion. An individual may, indeed, forfeit his liberty by a crime; but he cannot by that crime forfeit the liberty of his children. What is true of a criminal seems true likewise of a captive. A man may accept life from a conquering enemy on condition of perpetual servitude; but it is very doubtful whether he can entail that servitude on his descendants; for a man can stipulate without commission for another. The condition which he himself accepts, his son or grandson would have rejected."

This kind of criticism was also found in post-war rhetoric local to the United States. David Cooper wrote the anti-slavery work A Serious Address to the Rulers of America in 1783, criticizing slavery in light of the "all men are created equal" right the U.S. was supposed to be founded upon under the Declaration of Independence:

"If these solemn truths [in the Declaration of Independence, e.g., "that all men are created equal"], uttered at such an awful crisis, are self-evident: unless we can shew that the African race are not men, words can hardly express the amazement which naturally arises on reflecting, that the very people who make these pompous declarations are slave-holders, and, by their legislative, tell us, that these blessings were only meant to be the rights of white men, not of all men: and would seem to verify the observation of an eminent writer; “When men talk of liberty, they mean their own liberty, and seldom suffer their thoughts on that point to stray to their neighbours.”"

Another slavery critic who wrote early in the post-war period was Alexander McLeod, a Scottish immigrant to the United States, arriving at the age of 18 in 1792. He wrote Negro Slavery Unjustifiable in 1802, which included the passage:

"This evil, prohibited by the divine law, Exod. xxi. 16, is equally inconsistent with what is said in the declaration of American independence to be a self-evident truth: ”We hold these truths to be self-evident-that all men are created equal—that they are endowed by the Creator with certain unalienable rights—that among these are life, liberty, and the pursuit of happiness—that to secure these rights governments are instituted among men.” In direct opposition to these self-evident maxims, the constitution provided for the continuance of the slave trade till the year 1808, and it still provides for the continuance of slavery in this free country."

Other anti-slavery texts made the same point throughout the antebellum period. William Lloyd Garrison often made the point, including in his 1829 An Address To the American Colonization Society, in his 1831 "Truisms" published in the inaugural issue of his influential abolitionist newspaper The Liberator, and in his 1854 No Compromise with Slavery. Others who made the point include the anonymous writer of "Letter IX" published as part of abolition activist John Rankin's 1826 collection Letters On American Slavery, the Rev. Charles Elliott in his 1850 book The Sinfulness of American Slavery, the politician Horace Mann in his 1852 Speech on the Institution of Slavery, abolition activist Frederick Douglass in his 1852 speech What to the Slave Is the Fourth of July?, politician Charles Sumner in his 1860 speech The Barbarism of Slavery, and many more besides.

Thus, pro-slavery advocates found themselves on the defensive on this point quite often, and would often strain to find justification to explain it away. As Tise relates in his aforementioned Proslavery... history, an early instance was written by Richard Furman, a Baptist minister from Charleston, South Carolina. In 1807, he was attacked at a meeting of Baptist clergymen by a "Rev. W. Mg." because he was a slaveholder and slave trader. As Tice recounts:

"To the assailant's query...that struck at the heart of the issue "Is it [slavery] consistent with the principles of the American Revolution?" Furman responded that "it does not appear to be consistent with the letter of one article in the Declaration of Independence; but however the expressions in the article may be apparently unlimited, it is certain they were designed to be understood in a restricted sense: For it cannot be conceived that they were designed to declare that children, idiots, lunatics, or criminals should enjoy equal privileges of Society with the rest of the community." Although he saw a limited social application of Revolutionary principles, Furman could not bring himself to overthrow its social ideology."