I remember when Twitch implemented the VOD expiration with the "highlight" system; the discourse at the time was that some people enabled VOD retention and then

I remember when Twitch implemented the VOD expiration with the "highlight" system; the discourse at the time was that some people enabled VOD retention and then forgot about it, uselessly clogging the servers. So if you really cared about retaining VODs, you just had to highlight them. I think they just counted on no one caring enough, since highlighting every single VOD is a pain. It turns out that most people who cared enough about retaining VODs just upload them to Youtube. Youtube is simply a better viewing experience for non-live videos, and it can generate some revenue (though usually very small, unless you have a huge amount of views). One problem with Youtube is that it's more strict about (what it thinks is) copyright content -- for example, some otherwise "free"[1] videogame music is regularly claimed by on Youtube by someone who sampled the original song, so it registers as someone else's content to Youtube's content ID. [1] By "free" I mean that original videogame music is not usually actively protected (even though it's under copyright), because publishers love when people promote their games.