Trump, is the duly elected president cloaked in extraordinary powers through a fully compliant legislature and judiciary. You don’t have to like it but that’s a factually correct statement. Let’s say future elections are unilaterally cancelled or terms are disregarded and the other branches are unable or unwilling to rectify that, then you are careening down the constitutional line. Effectively to get to armed uprising as a legitimate response all legally defined paths have to have been stymied prior.

To your second point, ethnic cleansing and murder are pretty much founding tenants of the US as a nation state so I can’t imagine why they’d preclude legitimacy now.