No. That's a great oversimplification that removes a whole lot of important details, and combines what was going on in Portugal with what was going on in Spain.

In the late 14th (from 1391) and early 15th centuries, there were waves of antisemitism that led to attacks on entire populations of Jews, with forceable conversion, in many cases. Basically, convert or die. Or just forced baptism, without the ability to say no. There have been a variety of causes people have posited for these particular waves of antisemitism. I won't get into all of them, from anti-semitic church teachings to fear of the other, but one rather practical concern was that Jews were allowed to loan money at interest to Christians, but Christians were not permitted to loan money at interest to Christians, meaning that a lot of Christians owed money to Jews, and were resentful as a result. Plus there were many wealthy and well-educated Jews that had important positions in society and there were a lot of people who wished they had those positions and wealth. In these attacks--pogroms--some Jews were killed, others had all their property destroyed and fled, while those who were forcibly converted could stay. But it was now illegal to loan money at interest. And while it was legal to be Jewish, it was a crime punishable by death to be an apostate.

So Jews who had never wanted to convert to begin with could no longer practice Judaism on pain of death, nor could they convert back. They might still have friends and family who were Jewish, too. This created an unstable position for both Jews and these converted Jews, who were referred to as conversos. It also had an unexpected effect, which was that Jews who had previously been ineligible for certain high positions in society, were now, as Christians, eligible, making competition more fierce. Jews were much better educated in religious issues than Christians, as far as the Old Testament went. So this increased resentment at these newly converted Christians. Some of the conversos embraced their new religion, while others did not and continued to secretly practice Judaism. A lot has been written about the people secretly practicing Judaism, sometimes called marranos. There are a number of dramatic old tales of these secret Jews, but the evidence that there were ever any such people in significant numbers is dubious. Instead, what we see is that as the 15th century wore on, and new generations were born, the children of conversos by and large were raised as Christians. But the old resentments against Jews continued and resurfaced. But in many areas, there simply were no more Jews, and instead the resentments were aimed at conversos, who were now called "conversos" even though they themselves were a generation or two removed from conversion. They were also called New Christians--the descendants of converted people. Christians who could trace their family back many generations with no Jews or Muslim converts, proudly described themselves as Old Christians. This was the first time that Judaism was seen as an inheritable taint. There were tests of purity of blood--lipieza de sangre--to show you had no taint of Jewish or Muslim ancestry, and there were positions in society only open to those who were pure of blood.

In this unstable environment, there were a lot of accusations of New Christians secretly practicing Judaism, because there were a lot of advantages to making such accusations. If found guilty (which was easy, given the tortures that were permitted in interrogation), half of their worldly goods went to the state, half to the person who had accused them. And the accuser's identity was secret, so the accused didn't even know who had accused them. Things that could get someone convicted included owning a Bible--something every Jewish household would have, but which Christians did not have because it was only priests who were allowed to interpret scriptures. Spending time with Jewish relatives, or having heirlooms of one's Jewish ancestors was also enough to get you convicted.

The logic behind the Inquisition was to finally ferret out all of the marranos so that all of the innocent, pious conversos would stop facing such accusations. In this environment, it makes sense that the chief inquisitor, Torquemada, was himself a New Christian. He felt resentful and threatened by New Christians who were secretly Jews, because they made all the New Christians look bad--even though, again, there was no good evidence that New Christians were secret Jews. In a witch hunt like this, there was no end to the accusations, so the goal of ferreting out marranos had no logical end--to be a New Christian was to be suspect. So the logic behind Ferdinand and Isabella expelling all of the Jewish in 1492 was the remove the influence of the Jewish community from the conversos, so the conversos would not have a potentially corrupting influence, or simply that they would not have Jewish friends and family around to possibly make them appear guilty by association. It was felt that getting rid of the Jews would end all of these poisonous accusations. Which it didn't.

So, yes, money was an important impetus for the inquisition, though these money issues really started in the 14th century, about 1391, but the inquisition did not start until the late 15th century, officially 1478. And money in and of itself doesn't explain everything.

As for the situation of Jews in Portugal--Jews remained an important and legal part of Portuguese life until 1496, when, under pressure from the Portuguese king's new Spanish wife, Portuguese Jews (and Muslims) were given the choice to convert or be expelled. However, when it looked like most were going to leave, the King changed his mind and most Jews then found their choice was between conversion or death, not conversion or expulsion. Jews were called to Lisbon as point of departure for their expulsion, but then imprisoned and forcibly converted or killed. Many thousands were killed, while all of the Jewish children were taken from their parents, forcibly converted, and sent as forced labor (basically slaves) to Sao Tome and Principe. The Portuguese inquisition was only established decades after this, and similar forces were at work there as had been at work in Spain, with similar results.