Hidden music files transferred from Android to Iphone

I moved from Android to iPhone about 7 years ago.

When I migrated from Android to Android I just synced the phones and transferred my files including music files. When I transferred from Android to iPhone I used the migration app and it worked fine.

The problem now is that I am on my 3rd iPhone (currently an iPhone 15 Pro) and those same music files have been copied from each iPhone to the next.

I have also manually loaded music from my laptop.

I would like to delete some of that old music, but it is nowhere to be found anywhere.

The music app on my phone can play that music and it will show up if I let the phone go to randomly play music, but it doesn't show up anywhere in the music app on the phone.

The music app can play Depeche Mode, but according the the Music App Depeche Mode doesn't exist on my phone.

I have also tried accessing the music by linking my phone to my MacBook Pro.

Still can't see it anywhere.

Yes I tried having the Music app show hidden purchases. That did nothing.

I have been using and hacking Macs since 1984 and have rooted around in the hidden system files thousands of time, but never on my iPhone. If I take my phone to an Apple store they will default to

"FULL RESET, DELETE EVERYTHING and Restore from iCloud" like they always do.

I'm not sure that will solve this.

The phone seems to treat these hidden files like some kind of sacred texts to be protected at all cost.

Why are these files hidden and why can't I just see them in a file manager and delete them?

Why don't any of the Apple store tech people know where these files are?

If the Music App can see them to play, why can't it see them to manage?

So weird.

Makes me miss the days of using Resedit to edit system files.