I think centralized social media is the reason we fucked up a lot of decentralized social media.
I was thinking earlier about Lemmy, and how when Reddit did their API changes everyone tried to rush to Lemmy. Which would be fine, except everyone tried to just recreate reddit. Everyone tried to make Everything servers. Do we need ten thousand Technology subs? Not really. But people just tried to all make large general purpose instances with all the generic subs. Because they feel like they have to recreate reddit--ALL of them.
Nobody needs to run a Whole Reddit. Something like Lemmy would have been better if 99% of instances were single or limited topic. Keep the scale small, keep the moderation focused and knowledgeable.
I remember checking out Revolt, which is a discord alternative, and I think it has the same scale problem. Discord has three basic levels: channels, servers, and Discord itself which is a collection of servers. Revolt assumes that you don't want to self host a server, you want to self host a Discord. You want to self host All Of Discord. I don't think that's the case for most people! They want to run their one server!
Decentralized social media can't take a centralized approach, you can't try to recreate these horrible giant bloated behemoths but now with less budget and less moderation. You have to relearn to think at a smaller scale, the beauty of decentralization is that we can link all these smaller scale projects together.