Here’s the thing about YouTube. From the very beginning, it was a video-hosting platform. Users create content. They upload the content to YouTube’s servers. Other users view the content, and upload their own. A simple formula, no? That’s why their pre-Google slogan was “Broadcast Yourself”. The thing is, storing video data long-term is expensive. This is where Google comes into play, because, unless you’ve got Google’s money, you cannot afford to store literally 100s of Yottabytes of video data, not for very long, anyway. Even if YouTube becomes a “mostly-worthless relic”, there’s nobody who can readily replace it. I suppose someone could create a fediverse version of it where you simply upload your own content to your own server and then sell (or give) access to other users, but it would be slow to start, and small as not everyone can afford their own server to host their content on. Or, a service that aggregates videos by scraping them from from video servers that it has access to, creating a hub for users to enjoy the content made by other users that is stored on their own servers.