I actually agree with you on the Amazon/Youtube/Meta thing and I’m trying my hardest to stop using all those companies, but I think another point here is that Twitter is much more directly connected to fascism, given that it’s owned by the guy who just spent a week crashing the post-election party at Mar-A-Lago.
You don’t just get to call any words that you don’t like, or even words directly attacking you, an ad hominem. A statement is only an ad hominem if 1) it’s attempting to refute an argument 2) by attacking the character/motive of the person making the argument INSTEAD OF the actual content of the argument. “Your argument is wrong because you’re an idiot” is an ad hominem. What the other commenter said to you is not. Note that people claiming “ad hominem” on statements that are not are sometimes said to be committing an “ad hominem fallacy fallacy.”
https://laurencetennant.com/bonds/adhominem.html