One of the difficult things in examining the Italian unification process is balancing on the one side the outright conquests by the Kingdom of Piedmont-Sardinia, and on the other the massive social unrest and upheaval which pressured the Piedmontese state to act as it did.

It's true that Tuscany was not as repressive as the other Italian states. There was no dangerous exodus of well-connected intellectuals to Turin as has instead occurred in the Kingdom of the Two Sicilies, Papal States, and especially Lombardy. Tuscany was also economically more prosperous than many other parts of Italy, and while it was not industrializing as rapidly as Piedmont or Lombardy, large public works and experiments in industry did occur.

But by 1859, the intellectual class all over Italy had been fomenting a narrative of unification for over two decades, to the point where it had become all-consuming. The Kingdom of Piedmont-Sardinia had already fought a war against the Austrian Empire, and once the Count of Cavour became Prime Minister the country committed enormous resources to transforming itself into a modernized state (albeit with inconsistent success, but certainly miles ahead of anywhere else in non-Austrian Italy) and had meticulously worked to present itself as a viable counterweight to Austria on the Italian peninsula to both to the Great Powers of Europe and within political discourse in the rest of Italy. The question, by this point, was not if the Piedmontese would unify Italy, but rather how they would unify Italy.

The intellectual class in Tuscany, much like the intellectual class in other parts of Italy, was not particularly fond of the political organization they served and ultimately looked upon Piedmontese annexation very favorably. This was in part due to frustration with Austria's cumbersome hegemony, and Tuscan government staff would habitually be subject to Austrian complaints ranging from censure perceived as too lax, all the way to foreign policy perceived as too disengaged. While the Tuscan attitude to these complaints was to politely ignore them, the (altogether true) Austrian presumption that Tuscany was a client state which only existed at their pleasure was no doubt a source of discomfort. When the threat of Piedmontese intervention against Austria emerged after 1848 (when the Piedmontese set a precedent by doing just that in Lombardy) the social dialogue in Tuscany rapidly warmed to favoring and facilitating Piedmontese hegemony, especially as political dialogue within the Kingdom of Piedmont-Sardinia was positioned around a nationalist narrative of expelling foreign influence in Italy (whatever the inner motivations of Piedmontese decision-makers may be). Indeed, social ties between intellectuals in Tuscany and their counterparts in Milan and Turin guaranteed common ground for shared identity, which eclipsed weaker notions of local identity and weak feelings of loyalty for Tuscany's Grand Dukes. Indeed, much like other post-napoleonic Italian states, the Grand Duchy of Tuscany vested an anachronistically large amount of power in the monarch, meaning the Grand Duchy's political class' enthusiasm was highly conditional on the monarch's own charisma and interest in government. But for whatever reason, be it conditioning to be passive given Austrian hegemony, strong kinship with the ruling house of Austria, or a genuine disinterest in government, even when the Tuscan monarch consented to reforms they were unable to earn the loyalty of the local intellectual class and indeed any reforms only had the ultimate effect of freeing social dialogue to further reinforce notions of inevitable Italian unity.

While the narrative histories often choose to focus on the grand designs of the day's important politicians and generals in the existential struggle to establish an independent Italy, what is sometimes lost is the fact that almost every initiative was in some way a response to significant social unrest. There would have been no First Italian War of Independence without revolts in Milan, and while 1848 was a year of urban revolts taking place all over Europe, Milan was not the only Italian representative of this unrest: in fact all over Italy, governments found they had to concede rights and constitutions, no doubt also because the Austrian "Forest of Bayonets" was presently employed in reclaiming Lombardy. In Tuscany, the important harbor of Livorno descended into open revolt, while unrest also troubled Florence, prompting the Grand Duke Leopold to replace his cabinet, and eventually flee first to Siena, and ultimately leave the country to seek refuge in Gaeta, in the Kingdom of the Two Sicilies. Leopold would only return after the war's end, escorted by Austrian soldiers, and his reputation was irreparably damaged in the eyes of his subjects both for his decision to flee the country, and his return escorted by foreign soldiers.

When war broke out anew in 1859 and the Austrians were again indisposed to defend their client states, activists saw their chance to revolt once more. This time, they were flanked by the leadership of the army, clamoring for the Grand Duchy to enter the war on the Piedmontese side against Austria. However, Leopold would only commit to neutrality, prompting his cabinet to resign and de facto allowing a military-backed provisional government to take power. The provisional government's stance was clear: Victor Emmanuel II of Piedmont was offered dictatorial powers over the Grand Duchy for the remainder of the war against Austria. A year later, a successful plebiscite for unity with Piedmont was held.

So in conclusion, the important take-aways would be that the Tuscan intellectual-political class resented the deference to Austria that was expected of them and the Army's officer corps also resented the monarch's reliance on Austria's military might (and while this answer is focusing on Tuscany, analogous sentiments existed everywhere else in the Austrian sphere). Coupled with a budding kinship across the intellectual leaders all over Italy as well as simmering unrest, the prospect of annexation to Austria's counterweight seemed the natural course of action.

Was there anyone of note who was opposed to this "natural" course of action? Not really. While the Grand Duke Leopold was not himself an unpopular ruler, along the machiavellian spectrum from Fear to Love he managed to achieve neither: unwilling or unable to develop policies which would placate or redirect revolutionary fervor in Tuscany, he did nothing to halt or counter the Piedmontese-led march to unity, but was also deferential and indeed reliant on Austria, while also doing nothing to actively defend Austria's hegemonic position in Italy. It is also true that inaction might just have appeared to be the less bad of all possible policy responses: unity was itself a vague concept which represented different things to different activist groups, and while it would never be able to be everything that the revolters in Livorno and Florence would expect it to be, it was going to be impossible to come up with an adequate policy response to every single grievance for which unity was touted as a solution. And ultimately, at the most visible turning point Leopold had welcomed Austrian aid to return him to his throne, even if he probably didn't need it (he had been largely safe in Siena). He could thereafter never repair his image as an Austrian puppet, and did not even particularly try to.

The sight of Leopold's modest baggage train departing the Pitti Palace in the Florentine suburbs seems to have stirred some affection in the Tuscan onlookers. But no one in the public sphere rushed to defend the deposed Grand Duke in any capacity. His own aristocracy rushed to be legitimized by the Piedmontese monarch as soon as the referendum for unity had passed. At the end, Leopold and his house had really only ever represented a weak-willed monarchy, perceived as entirely reliant on the Austrian Empire for survival. There were no questions asked of Leopold's character, as he had long proven himself a mild-mannered monarch who when buffeted by the currents of revolt on the peninsula had implemented the reforms asked of him to the extent that he could, but he has also proven all too accommodating to (and reliant on!) Austrian hegemony. The political narrative in Tuscany, as in the rest of Italy, agreed that for the sake of the Italian people it was time for even the most agreeable local monarchs to step down and leave the stage free for the monarchy which would instead build a new country for the future.