I have noticed similar patterns across different individuals. Motivations may vary, however the modus operandi is the same.
Those individuals lurk around in chat-rooms all day. They interract with people in a way that tries to undermine them and make them feel bad.
The generic approach is to have random chats from time to time, however the difference is that their purpose through those chats is to simply build rapport to the people they're talking to. Making them actually engage.
After this, they keep acting in a demeaning and belittling manner towards the other people. At this point, if the other person replies in kind, they keep pressing around the same ideas until the other person either gives up and just accepts that that's just how they are, or keeps engaging in this combative dynamic.
I believe people that interract this way have turbo-autism, as I would define it.
The framing of the interraction is shifted to an ego-based one. Rather than doing what you wanna do, or talking about what you wanna talk, you become coerced into either defending your reputation, or getting some revenge for their transgressions on your person.
Neither of those is optimal. Because you just get reframed into doing what someone else wants you to do, manipulated, even.
It's interesting for me to see what exactly is the end game of this sort of behaviour. I think it's rather lonely.
What motivates such a model of interracting with other people? It's clearly dysfunctional in my eyes. People generally do not tolerate this, and stray away from the ones that exhibit it.