I don't think Trump cultivates a cult of personality any more than Hillary or Bernie do, really. With Hillary it's especially obvious: instead of identifying themselves with a movement or a cause, many (of course, not all) supporters use slogans like #imwithher, referring to her specifically, or it's her turn, as if she deserves presidency. The Bernie bird ordeal is just as bizarre as the girls singing for Trump, and even the girls aren't singing fascistically (compare them to something like Triumph of the Will: the girls are supposed to be cute cheerleaders, which is creepy and fascistic insofar as all cheerleaders are creepy and fascistic, but are not meant to evoke national/political/social unity and strength).

With regards to turning people within the same class against each other, this has always been the strategy of the bourgeoisie. The IWW accused the AFL of doing so back in 1905. Hillary's neoliberalism does exactly the same thing, but in a more muted way: you should rally around your identity and get marriage equality, instead of finding solidarity with other proletarians! Furthermore, Trump and most Trump supporters I've talked to actually think the opposite: they see Trump as wanting to build inter-racial cooperation (of course, they see BLM as divisive) for American citizens. While this is attempted through conservative politics and will not succeed, it is nevertheless not fascist in any sense.

I do not think that he is similar to past dictators. Hitler is an oft-raised example but that is pure hyperbole: can you imagine if Hitler, or some modern European alt-rightist, hosted a Jewish or Muslim restaurant at their headquarters, and propagated an image of them eating there with the caption, "I love Jews/Muslims!"? That would be ridiculous. There is a major difference here: Trump is anti-illegal immigration, but fairly consistently pro-expansion of skilled immigration, meaning that he does not think the American nation must be preserved, but that America should be competitive economically with other countries. This is markedly different not just from racial fascism, but also from more subdued national fascisms like Brazilian Integralism, which uses militaristic and spiritual rhetoric about overthrowing the existing economic system, not getting better within it.

Furthermore, he has made no attempts at undermining American democracy. His diatribes against "crooked Hillary" are actually pro-democracy: he rallies against the ossified establishment that no longer listens to the people. He has said that he should win, because "everybody loves [him]," not because the people who don't love him should not have a say.

While it is true that Trump prioritizes the lives of American citizens and prefers the preservation of American values, this is true of literally every other presidential candidate, ever. No presidential candidate will ever say, "why don't we make sure the Mexican workers are doing well?" (unless that is specifically useful for American strategic interests, like in post-WW2 Europe and Japan) or "why don't we overthrow American values for new ones?". Given the nation-state system of global politics, this simply makes no sense. Trump is fascistic, as in he is nationalistic, insofar as everything is nationalistic.

With regards to stability, I do not have extensive enough historical knowledge about past political reshufflings in America, although I do suspect that Trump is a lot more skillful and clever than some people think he is. FDR famously reorganized the American system with the New Deal, and though that was disastrous for the communists, it was decent for most of the American population.

Finally, about the progressive potential of Trump. Basically, he stands against neoliberalism, which means potentially an end to the unproductive identity politics of the last decade, both on the Right and the Left. And, his support base, being mostly non-racists and non-fascists for the reasons listed above, have a real beef with the existing system. We must ask ourselves: why do otherwise rational people support a conservative candidate instead of their actual class interests? The rational kernel of Trump, for some, is that no Left alternative exists to seem feasible. Given the failure of Sanders both to set himself apart from the Democrats and to win, Trump is the oppositional party in the absence of a Left. What this implies is not to support Trump, but to provide a Left alternative in order to recruit from Trump's own support base.