I don't think he is a buffoon per se. I think he is an egomaniac and that allowed him to get caught up in something akin to the umpire scene from the Naked Gun. Each time he got more over the top and people ate it up, it fed his ego and he tried to top that.
Personally, I think that quite a bit of the GOP establishment pushback against him is more rooted in not wanting to be associated with the deplorables than it is anything else. You had people completely flip and start arguing the opposite of everything they used to argue and say, "well because Trump..." Ok, well if Trump said he liked chocolate cake, that shouldn't fundamentally change your views on chocolate cake. What it was really about, IMO, is that Ttump gets support from the one group in this country that all the other groups are not really fans of and there is the added bonus that you can say whatever the heck you want about them and not get a blowback because of their akin color. Poor whites. All the epithets that get thrown at the MAGA types are the same things you have always seen thrown at poor whites. "The people we think are ignorant and we don't want to be associated with are part of that party so we want out...I mean, the party was still operating as it had been operating since at least GWB but..."
As to the guy that went to IU, a Chinese guy just shot up a Taiwanese church. He was connected to the Chinese government through organizations they have set in the U.S. He wrote a manifesto about dealing with the Taiwanese issue (using China's verbiage for the issue) and not a word. Didn't fit the narrative. The Buffalo shooter said he was an authoritarian leftist and basically a radical green. He also harbored racist views so we have to change the GOP? That's just dumbassery.