Much further back… Abraham Lincoln was a Republican. The party was founded on anti- slavery. The current party has nothing to do with the original party.

I think while the general communities have made it, a lot of niche communities failed to attract enough population to keep on generating more content. As an example, just search for the "Imaginary" series of landscape art communities on the Fediverse (eg. ImaginaryVistas). Many of them don't have any recent posts or 1 post per days or weeks. That's not enough to keep people invested. Even the largest digital art community is still mostly carried by 1 person.

It looks like it could fall over with any gust of wind and kill someone.

Should the instances that responded to you be refederrated? I’m pretty sure I saw some of them on lemmy.world’s block list. I think it would be sad for these small servers to not realize they are, in fact, not connected to the greater fediverse. On the other hand, if you’re an admin, and you don’t know what you’re doing to the point of not knowing your server was infected by hundreds of thousands of bots, maybe it’s too dangerous to refed.