Fine, you are welcome to stay with the meme enjoyers. It makes me wonder why you are not on reddit. If reddit "does it so well" why didn't you stay on reddit?
I'd at least hope you were arguing in good faith, but you're obviously not. I pointed out specific features of Reddit which, in my opinion, worked fairly well, and I pointed out how they could work here as well. That doesn't mean I had any reason to stay in Reddit.
You've mostly deviated from the subject and assume that most people are exactly like you, hate memes and all "thrash" content - by your definition that everything you dislike is thrash. I disagree with that. I think most people like generalist topics, thus why they flow towards those communities.
Mastodon, having existed for longer, is a good example. The main generalist instances are far bigger than the specific tech or art ones. But, because they haven't defederated from each other, everyone can sit in their favourite instances, in which the local content most suits their tastes, but still interact with one another. You can go on fosstodom and mostly see FOSS related topics on the local view, while being able to interact with more generalist instances like mastodon.social at will. If fosstodon had defederated from mastodon.social, it likely would've lost many of its users as they'd probably not like being in an instance that forbids general content.
Being in an instance with people who share similar topics is fine. Defederating from general instances, though, just puts you in a small bubble. I don't understand why you reject that any other solution other than defederation might work when it has worked for Mastodon, Pixelfed, etc.