I wonder if you have any insights that could help other trolls become former trolls?
Any way that one could somehow engage with them? Trolling back again or undermining them in the way they undermine others surely isn't the solution, is just "one upmanship" at the same game.
It's just a thought, and for someone who is totally over trolling I'd imagine, suggesting it because sounds as though you are - maybe not something to attempt if one thought it might take one back into a trolling outlook again.
Whether that can be a startup I don't know. Maybe a bit tangential to your question, just a thought.