Will be interesting to see Apple's response to this, surely they are going to have to either offer a HiFi service of their own on Apple Music or say why they are not doing so? Makes for quite a dilemma for me. I've had an Apple Music family sub for ages, now part of my Apple One Premier plan. However, I've been pondering a switch to Spotify for 2 reasons:
1) My car doesn't support Apple CarPlay (grrr) but has Spotify Premium built in with access to the entire Spotify library, ad free and unlimited data. If I had my own Spotify Premium account I could play my own playlists in the car as well as everywhere else.
2) I've gotten increasingly fed up with my HomePod stereo pair in the living room not maintaining their pairing. Constantly having to reset one or both of them. So I've given up and bought an alternative compact hifi that supports both Airplay and Spotify Connect (and CDs, how retro!) I'm led to believe (yet to test it) that Spotify Connect will give me better audio quality than Airplay as it plays direct from the server rather than the phone, and it also means I don't run the battery down on the phone.
So, Spotify HiFi via Spotify Connect would be a potential 3rd reason to consider switching if Apple don't respond.