OK thanks. So this is a good example. This friend lives in a Red state and he found Jesus, which is two factors that would strongly influence him to be Republican voter. So I don't think this guy would be voting Trump in response to getting dragged by "the left" online. He's a conservative Republican, in a red state and Trump is the Republican nominee. That's why he, and guys like him would vote for Trump. Incidentally, I don't think its too controversial to say that this is the main reason people are voting for Trump. They are conservative and/or Republican and Trump is the Republican nominee. There may be much more numerous, varied and complex reason why they are Republican and/or conservative, but their main reason for voting for Trump is just his party affiliation.
That's a very cliff notes version & you have causally wrong, he didn't vote Trump becomes he became religious, he dabbled in Christianity because it was trending among right-leaning type young people, he would've been similarly moved by Romney. I'll explain more below.
I don't right now, but I will give it a watch and comment later, thanks for the video.

It was a weird thing to watch in real time (an internet famous person become radical in front of everyone's eyes)
Right, but I'm not disputing any of that. Again, what I am addressing/disputing, is the claim that criticizing people online turns them into Trump voters.
Of course criticizing people changes them.
Back to my friend, he's broke, paying off debt, working full time job plus driving Uber plus in school for massage and for 18 months living in his car. He sees online left culture talking about his white-privilege and being generally impotent/reactionary (picking apart cultural norms as reactionary without having anything solid to offer to fill the void) and then online right culture talking about working hard, embracing masculinity, 'traditional values' and veers right. When he posts about this type of thing in FB he gets a lot of flack (you know how people online are). So this pushes him further in that direction. It happens every day & isn't limited to politics. Think about the things your parents criticized you for, I dunno about you but some of the things my parents judged me for I take pride in now, it's just human nature.
I simply reject the notion that criticizing people on the internet "changes" them into Trump voters.
It's not like a magic wand, more like a repelling magnetic force. You see someone who represents something and they act like a dick so you move farther away from that.
Huh?
You are
"blaming it on someone else", you literally just blamed in the prior sentence that I quoted right above this and I quote "online leftists" and their quote "extreme in-groupism & purity testing". You don't see that this is you, explicitly blaming "the left", "criticizing people online" for those people voting for Trump?
Description isn't 'blaming'.
Say there's a kid who's a bully in school. You could point to neglect or abuse at home as possible factors for why he became that way without saying "it's all because of his parents".
I think you're missing my point, if someone thinks they genuinely like Trump they're not gonna
blame anyone for that. Like if a someone has an abusive boyfriend but think they're in love they're not gonna blame someone, they think they're in a good situation even though an outsider can see it's toxic and be curious about what led up to it.
Are you OK?
What?
My guy, you literally just said, quote " it's seen by you". You can't say that and then try to sweep it under the rug by saying "I'm not saying", what you literally just said. On a related note, this is a pretty spot on example of what @Gori the Grey very articulately and succinctly hit upon. First, I will quote him rather than paraphrase:
I don't know your exact beliefs so I'm giving you the benefit of the doubt.
Someone can come off in a way without actually being that way.
If people could see that the world would be a much calmer place.
And on that polarity, Narz is correct: it's the censoriousness of the one side that drives people to the other side.
It's almost like ******* on people as a political strategy doesn't work.
Why did Regan and Obama win so hard? They actually had things to say. They stood out in their own right. Obama wasn't saying "well... at least I'm not Romney, what a schmuck amirite?" he was like "I'm Obama bit**es!".
Clinton, Biden, Harris exist mostly IN OPPOSITION to Trump. I'm too lazy to use Google Trends but in 2021-2023 how many people who thinking about/searching about Trump vs Harris (10 to 1, 30 to 1)? Even tho Harris was actually in the White House (well working there, does the VP live there?). Nobody thought about her.
The vacuum of charisma in politics opened the door for Trump.
Not to say I personally think Trump is charismatic. I find him caustic to listen to. But as a cultural phenomenon he's interesting. And he's absolutely benefited the news media and given us all something to distract ourselves with and given society as a whole an excuse to drag our heels regarding the important issues. When you can spend 70% of your time saying "the most important thing is I'm not this guy" it makes your homework much easier.