Yt-dlp usually rips the best quality possible from the source. Going to a private tracker won't magically make quality better than where the artist posted their music. Or do you think yt-dlp only works on YouTube? (You would be wrong about that as well)
Which music library can it rip from? Last I checked it couldn't do spotify's due to the heavy DRM they use. All the tools you find online either do an audio out rip-and-reencode (lossy though minimally so) or more likely "look up on YouTube Music and download" which is objectively going to yield worse audio quality (though whether that matters for one's usecase is very dependent on hardware and wetware specifics). The bigger problem with blind YouTube music rips is you're occasionally going to end up with intros/outros and random diegetic noises from music videos.
Lidarr so easy to set up though. And gosh I wish I started listening to full albums sooner, cherry picking the radio singles really leaves out a lot of bangers
i believe there is a way of using lidarr with yt dlp called lidatube, used it for a bit but have abandoned it and have lidarr prioritize usenet over other sources
my ears are shit and I have no perception for detail, so I genuinely can't tell the difference between the nice audio files and the youtube equivalents