I want to save every video I like on YouTube?
Youtube deletes everything eventually. I need a way to save all videos I like across mulitple accounts into somewhere safe. Obviously cloud would be too expensive so I'll probably would have to make local NAS Raid 1 10 Tb setup or something. But is there a service? That charges like $10/month max. Would that service be safe from DMCA?
I think YouTube has a big public playlist of all your liked videos. Feed it into yt-dlp and choose a good format (eg. yt-dlp -f "22" "youtube.com/your/playlist/here"), and it will spit out all the videos in the playlist to whatever directory you're in.
If you're willing to sacrifice some quality, it seems feasible to just download and store it locally. At 500 kbit/s for mediocre standard definition, it works out to about 200 MB per hour of video. At that rate a 4 terabyte drive would store ~20,000 hours or ~3 continuous years worth of video, which is probably several decades worth of typical YouTube viewing, assuming you watch the whole clip.