YouTube get 700,000 hours of video uploaded every day. That's 4.3 PB added per day. You may need more than a few dozen TB...
https://www.reddit.com/r/AskProgramming/comments/vueyb9/how_...
I can imagine if they've added rate-limiting, e.g. 30GB per IP per week - that would've reduced amount of crap, literal white noise and spam/scam videos uploaded to Youtube in several magnitudes. Another strategy is, if a video doesn't get 1000 views after a week - it's deleted.