It is actually even deeper and worse than that - I think we do not fully understand the angle that the internet is a massive anonymous playground for some of the worst people of humanity. A gigantic Petri dish for highly manipulative sociopaths who thrive on causing misery for others. I suspect way over half of the internet mobs, the cancel culture and other vigilante pseudo-justice is being fueled by sociopaths who just want to destroy others.
And knowing that, you then need to understand how these people think and work. There is no reply you can give or action you can take that will not give them at least SOME satisfaction. Any form of engaging in discussion, no matter how skilled in rhetorics, and you are losing because you reacted to them and they got a rise out of you. Downvote, block or ban them? They enjoy your reaction and know you are a potential source of entertainment for them, so they will find new ways to get to you.
The only thing that completely destroys these sociopaths is what OP said: ignore them. Complete deafening silence. No reaction at all. This breaks their spirit worse than anything else! Do not feed the trolls was always true, we just never saw how many of these trolls are highly manipulative, targeted attacks from sociopaths trying to feed.