Obviously this is all counterfactual projections at this point but I think there would have been a ton of confusion and when confused people tend to stick with the status quo. I hope I would have been wrong but I think there's a strong chance that people would have given in and when later it turned out to all be bullshit we would have had a Very Serious Public Debate about how Trump was an illegitimate president and then not done anything.
Ironic that I find myself arguing that I think the US system is more robust than that. Given that I've always thought the US political system was massively flawed from its inception and that I have long thought the US is possibly the developed country most likely to go fascist (though there are other contenders, including us, I think the US edges it, and I'm not counting Russia as a 'developed country').
But there are clearly a lot of people in important positions within the US system who _do_ value democracy, and I just think to truly bring about the dstruction of it would require someone with the instinctive cunning and talent for political manipulation of an Adolf, and Trump just does not seem to me to have that.
Above all, he is not a long-term thinker or a concientious schemer. The thing that is alarming about his shenanigans is that it's not only those who want to see democracy survive who will have learned lessons from his failure. The whole thing would have provided lots of extremely useful data for anyone who wants to try again at some point.