I use yt-dlp (and back then youtube-dl) all the time to archive my liked videos. Started back in around 2010, now I have tens of thousands of videos saved. Storage is cheap and a huge percent of them are not available anymore on the site.
I also save temporary videos removed after a time for example NHK honbasho sumo highlights which are only available for a month or so then they permanently remove them.
I also save temporary videos removed after a time for example NHK honbasho sumo highlights which are only available for a month or so then they permanently remove them.