I block many users and that seems to solve most of my problems with negative people. Like psyop type trolling of any kind I block or if someone is just an ass. I don't even reply. If they really piss me off I reply and immediately block so they can't even respond. I've had a few go through every post I've made in a month trying to down vote everything. That, now that, I get a kick out of myself. I never start the BS though, or at least I do not think I do or intend on it.
Also, use Alexandrite the 'a.lemmy' version of the interface. It basically ignores the downvote trolls by design so you won't even see their stupidity. This interface makes this place much more enjoyable overall.
Back a few months ago I was about ready to leave over negativity, but using a.lemmy.world completely shifted me in the other direction.