I think it is very difficult (and dangerous to the host) to serve user-uploaded videos at scale, particularly from a moderation standpoint. The problem is even worse if everyone is anonymous. There is a reason YouTube has such a monopoly on personal video hosting. Maybe developments in AI moderation will make it more palatable in the future.

The "host" is the user in this case. Every user that watches the video, shares the video. Given that discovery doesn't appear to be a part of this platform, any links would undoubtedly be shared "peer-to-peer" as well, so if you aren't looking at illegal things and don't have friends sending you illegal things to watch, it's perfectly safe.