Note that I'm obviously not saying any online discourse is for naught.
But during and after your "social media experience", for lack of a better term, do you feel better or worse, and if not better, did you at least accomplish something?
But you have to then be honest about the answer to that. Especially if religious or political conversion is what you hope they get.
This also goes for answers to tweets, where even on highly technical, niche topics, a pretty large share of the replies seem either performative ("I'm going to ask a question to impress OP, the answer does not really matter!"), or useless (some tired meme, if it was ever funny), or just plain nonsense ("I don't really understand the technical matter behind that, but here's some nonsensical technical question that seems vaguely related").
I think in face-to-face social situations, most people would be much better at weighing whether their interjection is worth the effort and the attention.