Counter point: only do social media (e.g. Facebook, Instagram, Twitter, etc) with people you know.

It’s the other crap, mostly commercialized, that is toxic.

There are things like http://www.classicshell.net/

Not sure if that’s what you’re looking for.

Sharry is a nice simple one that I think hits all your points.

Not serious, but amusing: https://hackaday.com/2023/07/10/gas-powered-fly-swatter-slightly-over-engineered/

We really need better sorting. My feed seems to be dominated by just a few communities rather than having a balance between all the ones I’m subscribed to.

And everything except “new” seems to stagnate too much.

There are probably specific communities that I’d miss, but the real answer is VOLUME. There’s still more content there.