Biden has done more to undermine the US empire in the last 8 months than Trump did in 4 years. Biden is exposing the contradictions of US empire in a way that Trump could never.
If Trump was president, then the mainstream narrative would be that the genocide in Gaza was simply because of Trump and Bibi's leadership. And you know what? Given how past presidents were able to rein in Israel when polite society started sympathizing with Palestinians, it would be believable. Instead, we get to see front and center, how a man that's been at the top echelons of us foreign policy for decades approves and supports genocide. This is the establishment's genocidal war.
In other words, Trump is perceived as an aberration, even when hes just continuing the same US foreign policy that weve been doing for decades. Moving the embassy to Jerusalem is still framed as entirely Trump's decision, even though he was just enacting a policy that Biden voted for in the 90s. And of course Biden did nothing to reverse that move, or even try to extract concessions to move peace talks forward.
Biden is damaging the "international rules-based order" in a way that would make Dick Cheney blush. Bush at least tried to put a veneer of international law on the criminal invasion of Iraq. But it appears the US and Israel are ready to burn the UN to the ground in order to carry out this genocide. Trump would be doing the same exact thing, except he would also serve as a scape goat for the liberal order (just get trump out of office, and we can go back to rule-following)
Don't get me wrong, they're both excellent accelerationist candidates. The world is watching two senile, hateful, egotistical vile men fight for control of the empire as the world burns.
Your view of intra class struggle doesn't make sense. Trump is a "little lower on the ladder" only in rhetoric. The executives of all banks and industry might view him as gauche, but he does just as much (if not more) to advance their causes as Biden. And talking about "banks eating industry" is about 50 years too late - nothing to do with trump
The classic model of petty bourgeoisie being the progenitor of fascism works well in America.
Petty bourgeoisie make up a large portion of the Republican base. Petty bgz themselves are the direct inheritors of the settler ideology and elevated position in society (thus it also includes many poor whites already "demoted" in social status). They feel the contradictions intensify from both sides, workers asking for more, and big bgz taking over. This puts them in a precarious position of becoming workers, so the petty bgz naturally act according to their (privileged) interests and become very reactionary.
An analysis of Trump's attempted coup on Jan 6th reveals the petty bourgeois make up of his supporters. He is a useful tool of the big bourgeoisie to resolve this contradiction.
So I think before attempting to analyze big bourgeois intraclass conflict, it's very important to consider the basic big bgz-petty bgz situation.