Also, with introduction of Apple Music, Apple disallowed sharing music over LAN. I always found it useful to be able to play music that sits on just one computer on the network, from any Apple device. What once just worked, now became a subscription fee for iirc $20/mo.
It pretty much looked like an extortion attempt: Apple blocked my access to owned, legal, lossless music files in their proprietary AIFF format and offered presumably the same music streamed from their servers for a fee.
IIRC this sharing functionality worked until Mojave and became problematic with the introduction of Catalina. It went from being an option in iTunes to being an option in the Sharing menu in System Preferences. It still used DAAP as an underneath technology but became problematic, with browsable but not playable library etc.
Before that, I had an IKE VPN set up from iPhone to home network which allowed accessing music residing on iMac's HDD while biking or hiking, on iPhone with much less storage than music library weight.
I do hate the apple tries to push Apple music at every opportunity even though I have zero interest.
Also, I found shuffle is broken in the music app. I switched to Foobar2000 and suddenly I'm hearing tracks on shuffle that the Music app had never played in 10years that were on my phone.
When I use Siri and instruct it to "play xxx", where "xxx" is a locally present song, it often randomly does not play the song but instead searches for it. An example from yesterday or the day before: I have a "Reservoir Dogs" soundtrack ripped from CD. If I instruct my iPhone to "play Little Green Bag", it no longer just plays the song it lists in Music.app, as it always did when it was called iTunes. It offers me the purchase and download of George Baker Selection CD which originally lists this song included in Tarantino's movie.
I currently have iOS 15.02 installed and I do not have nor had Apple Music subscription.
Settings->Music->Show Apple Music