Yep, I am still on IOS 13.1.1 but this issue was introduced with IOS 13.0. I am surprised that is still not fixed (I don't support subscription music either for the same reasons and have hundreds of locally created Itunes playlists synced to my phone). Same with the mail issues people have been complaining about them since IOS 13 released. I am happy I dont use the mail app and use GMAIL instead or else I would be pissed too.
Itunes previously used a lot of non-standard interpretations of the ID3 tags in mp3s. It's possible that Apple Music is now using a different interpretation of those tags, which is not necessarily a bug, but it would definitely have the chance of messing up things that were fine before.
For example, see:
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What's this "Album artist" tag iTunes uses? Any way to set it using java?
iTunes uses an ID3 tag called "Album Artist", and for one album to be actually grouped as an album in iTunes, both the Album Name and Album Artist must be the same. As far as I'm concerned, Album ...
You can batch-fix ID3 tags with this tool, but unless you know what's changed on Apple's side, it might not be super helpful.
Mp3tag - the universal Tag Editor (ID3v2, MP4, OGG, FLAC, ...)
Mp3tag is a powerful and easy-to-use tool to edit metadata of audio files.
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