I have a folder of MP3s, some of which date back to 1999, just a few years after the format was popularised. Most of them have utterly terrible names (think RIDEONAM.MP3). I think at this point they might even survive the heat death of the universe. And they’ll still be terribly-organised.
You can probably find a converter that will rip those files from Youtube for you. I did mine a year and a half ago. If I open Spotify it’s just to see the playlists they made for me, because those are actually pretty good, but I rip those files and store them too.