It seems like every other video hosting solution that the fediverse tries either buffers endlessly or refuses to load entirely.

I mean, I can view PeerTube videos. There is some decidedly fringe and bizzare content on PeerTube, and in general, it's short of things that I personally want to view, but my problem isn't "I can't view the video".

I am very skeptical that PeerTube is going to be a viable YouTube alternative in the way that the Threadiverse is Reddit. Video costs much more money to transport than text. YouTube has a way to make money from their viewers. I just don't believe that a handful of volunteers are going to come up with enough money to fund global unicast video distribution. Yeah, maybe over time bandwidth grows cheaper, but then YouTube is going to be running higher-res content or 3D content or God knows what.

But, viability in the grand scheme of things aside, PeerTube does work for me, at least to the extent of being able to view video streams.

Also, fuck catbox.moe, those links never fucking work for me. I’m convinced they have my VPN blocked, because every single catbox link is completely dead.

I'd be more-inclined to suspect that your network provider is blocking Catbox.

If you're on Linux, the mtr-tiny package on Debian (and maybe other distros) has the mtr command, which will basically run repeated traceroutes, and can run using TCP rather than ICMP packets. You can run $ mtr --tcp --port 443 catbox.moe to see if HTTPS packets heading for Catbox start getting blackholed.

If the packets make it all the way to one hop short of Catbox, then it's probably Catbox blocking. If they stop before that, then it's probably your network provider.

Strictly-speaking, there are other ways that you could be getting blocked, but this is the most-straightforward way to do it, at the TCP or IP level, so if you are getting blocked, that'll probably show you a breakdown.