Sounds like you set up your comm poorly and you really don’t want people to interact with you on it. That’s fine — you should learn how to set up your comm properly so you’re not butting heads with people who disagree with you. And maybe, if you don’t run the instance, discuss with those who run the instance if they’re fine with you squatting on the name ‘politics’ and not letting others interact with it. They might be fine with it, they might want you to call it something else so politics can be actively discussed in that comm.

Voting is kinda dumb on Lemmy and I think it’s only there because it was on Reddit. Voting doesn’t give future posts weight, and if you run the comm, downvotes shouldn’t affect your ability to post there anyway, and I don’t think it would on Reddit, either. But on Reddit, a lot of downvotes can hinder your posting. Lemmy doesn’t do that. So personally I hide them, and only upvote helpful/kind posts, and only downvote exceptionally rude ones. And I don’t care how others vote on mine or on anyone else’s. I sort by chronological. You could have 50,000 downvotes and I’d still see your post in order by time. (I doubt you have that many.)

Trolls are an inevitability. But how they affect you is largely your choice. Stoicism goes a long way online. I’m not saying don’t care, I’m just saying give the words (and votes) of others the emotional weight it deserves: next to none. Don’t let it affect your day.