I agree, but unfortunately, there's probably not a good self hosted solution to this specific problem.
I use musicbrainz for music tagging, which is an excellent source for all metadata except lyrics. For better or worse, the only decent sources of lyrics seems to be genius and musixmatch, and neither integrate well with tagging tools like musicbrainz Picard.
If anyone else has found an easier way to do this, I would love to hear it.
I'm not sure if the application is safe. It may be malicious. Proceed at your own risk.
I saw a GitHub project called 163MusicLyrics that's sources the information from Chinese sources (NetEase and QQ).
The entire software is in Chinese, but the results looked really accurate from the sandbox I ran. It's even actively developed with v6.2 releasing least week. But again, I don't know if it's safe.
I'm not good at code but it looks like it's OSS, so you could verify the code yourself or reverse engineer something with the API calls they use?
Let me know if you come across something though. I'm also looking for a way to get LRC files easily.
EDIT: Also for self hosting, I use Jellyfin with Symfonium, and Tailscale. It works great for me and has been relatively low maintenance.
When listening locally on my computer I use foobar2000 and the OpenLyrics component - but yeah, it falls short sometimes unfortunately. I've written myself some scrapers that crawl some sites, but that still requires a bit of manual intervention. I'm still looking for a self-hosted app that can help with tags though, and more in a manual manner; I don't really like a script assuming that this album is this specific release when it might not be.
Besides, some files have the lyrics already in the tags - often the case when buying/downloading for free from Bandcamp.