The music on YouTube isn't any more piracy than unblocked Spotify. YouTube's "official" music uploads (these that are a square with a blurred background behind the square) are acquired by paying DistroKid or record labels. Unofficial uploaders usually aren't monetized, either bc they didn't enable it、are niche、or got ContentID'd by YouTube. Those few that are monetized(e.g. Si𝚕vaGunner and Gi𝚕vaSunner (i.e. not Si𝙸vaGunner or Gi𝙸vaSunner)) usually get DMCA'd eventually.
Downloading from YouTube is piracy though, though like OP says some don't think so for some reason.
https://appledb.dev/device/iPad-2.html Select 9.3.5 and choose the jailbreak method you want. After that, download a newer browser with the jailbreak or even just run Linux on it.
In my opinion, it stacks up VERY well, even better, except the toolbar is by-default a mess for some reason while there's a very easy option to set it to tabbed.