PeerTube is federated and moderation is each server's own responsibility.

It doesn't. It also has no defenses against DoS attacks, intentional or inadvertent. It is the perfect software for people with no experience distributing videos.

this would be a major hinderance to widespread adoption. DoS attacks aside the fact that it has no legal liability offset for video hoster (which anybody watching the video ends up sort of like bitorrent)

It works like forums, you need to look for an instance with the culture and moderation of your liking.