Even if everything you have said in this post is 100% true (and in my opinion, it is not), then the good news is that both Lemmy and kbin (and really most federated spaces I've joined) have excellent blocking tools. Block freely, block safely, block often if these other posts are bothering you.
I quickly looked at your kbin account, and it seems like every post you've made so far has to do with social networks and apps and people being mean. I know it sucks that you've just lost a very large community, but trust me, just let it go and you will be happier.
I have no way to know if you'll do this, but just as an experiment: next time you see a post here that you think either comes from or belongs to The Old Place, block it immediately, and then open up Magazines (or channels if you're in Lemmy) and pick a topic that normally would not interest you at all. Birds, movies, books, architecture, science, stamps, etc. Browse that for a few minutes and try to involve yourself in one topic. Just one. Even if you know nothing about it, ask an insightful question. It doesn't really matter if you get any response at all or not.
Do that a handful of times every time you see something you do not like here. I'd be curious if it helps you (or anyone else that tries this) in any way. I have done this myself, and it has helped me, but that doesn't prove anything.