It affects me because I feel I need to keep up to date with which instances defederate with each other in order to follow communities. It feels like defederation is a cudgel that is thrown around a lot, and a lot of innocent people get hit in the crossfire.
However, you are correct. A lot of my posts on Lemmy have, to be honest, been my attempts to fix something which can't be fixed. It's super not a healthy thing to be doing, honestly. I really should take a break from Lemmy, it's done nothing but cause me stress and tire me.
Edit: Bit of context for those late, my original comment was just a ramble about how I'm fed up of drama, etc. Nothing really that groundbreaking, tbh.
I've not seen it myself (not being an admin), but I think there's a "remove" (not purge) button on the community page. It clears all the posts from that community, and prevents new ones from being received.