Hopefully there is more they're fixing.. I recently posted on StackExchange (with no answer yet) that I have a very large iTunes collection from years of collecting and ripping CDs. In the past, "Get Album Artwork" usually did a decent job, but not always. If I look back about 10 years, there was an old script called 'FetchArt' which plugged into iTunes and did a great job of filling in the gaps that iTunes couldn't on its own, but I think it has gone way-stale at this point.
When I upgraded the library to Catalina's Music.app (because iTunes was removed during the upgrade), Music.app spent quite some time going through my library and attempting to "fix" all my album art. Unfortunately, it seems to have done a horrible job at that in that all albums by a few artists that I checked seem to now have a adopted a single album cover from one album (e.g. all Iron Maiden art is now "Piece of Mind", all Peter Gabriel is "So", Red Hot Chili Peppers "Californication" has picked up a greatest hits album cover, and so on).
I'm just generally upset with Apple now because their bad coding/algorithms undid lots of automatic and manual work that I did over the years to get the right album art attached to the right songs in my collection. If it wasn't for the fact that I have about 50,000 songs in my library (yes - they're all legit believe it or not) I'd just go about it manually, but this is overwhelming and upsetting. With a company as cash strong as Apple, you'd think they'd throw a few bucks at the QA department? >sigh