Twitter never cared about users rights. Read Matt Taibbi's congresional testimony on Twitter's censorship machine.
These are not serious people.
Even though OP didn’t provide them, I can think of many supporting examples for their assertion that Bari Weiss and Matt Taibbi are either intentionally operating in bad faith, or stupid, or both. So this does not at all meet the definition of ad hominem.
Put another way: “you’re wrong because you’re stupid” is an ad hominem. “You’re wrong, and I think you’re stupid because [reason]” is not. This holds even if the person making the argument does not explicitly give the reason.
You're deliberately overcomplicating things to obfuscate the obvious fallacy.
No, this is a common misconception. Addressing the speaker is part of it but is not sufficient by itself.
People who are quick to claim “ad hominem!” have been getting this wrong basically forever, so please feel free to educate yourself by reading this excellent post: https://laurencetennant.com/bonds/adhominem.html
“It is not a logical fallacy to attack someone; the fallacy comes from assuming that a personal attack is also necessarily an attack on that person's arguments.
Therefore, if you can't demonstrate that your opponent is trying to counter your argument by attacking you, you can't demonstrate that he is resorting to ad hominem.”
Very funny when you think about it, but sad too
You claim about fallacies later, but this is a also a fallacy.