They totally destroyed the audiobooks feature. Can't edit ID3, no playlists with Catalina. It's hard to believe how they could destroy it so thoroughly.
That said, of all the people you know in the Apple ecosystem, how many people know/do the following: know what an id3 tag is, manage the metadata of their digital audio content, listen to audiobooks. Maybe I'm wrong, but most non-nerds I know don't and would not ever want to think about 1 and 2. Plenty of people who fall into 3, but again all people who don't like or work in tech that I know use audible or the public library or some other service.
I like so much about Apple products, but my big and growing fear is that my needs and the needs of the kind of person who edits ID3 tags are constantly being subsumed by the much larger portion of their customer base that has no need and no desire be involved in anything like editing file metadata.
Of course I have no idea if this is reflected in the world-wide breakdown of Mac users, but I'd be surprised if the 'programmer' category isn't sizable enough that it's kind of silly (in a typical Apple way) to ignore them.
It’s hard for me to believe that Apple is or even can dedicate the resources I want want to the laptop/desktop line when iPhones alone make 80% of their revenue. I’ve mostly switched to linux with a windows box when needed.
You could say the same thing about using the Terminal.app - removing everything but the most widely and commonly used features is a foolish strategy. The sum of all niche audiences still makes up a significant user base.
That said, even as someone that carefully maintains a rather large and growing local music collection I'd almost agree with you and be fine with a stripped down Apple Music app since anyone serious about that interest probably uses one of the superior and more in-depth music management options out there. However iTunes/Apple Music is still required to sync that music to your iOS device. So while I'd have no problem completely replacing iTunes/Music.app with any of the more feature-complete options I can't. I have to use it, even if it's just for syncing and apparently it has lost quite a few features since Catalina (haven't upgraded yet).
In other words: If Apple doesn't care about the kind of users that maintains a local music library they shouldn't hold them hostage by only allowing to sync said library via their otherwise barebone app. It just means I have to manage my content in 2 locations.