The idea has ~5k votes and 137 pages of comments on their forum and yet no action from Spotify.
https://community.spotify.com/t5/Live-Ideas/iOS-Implement-Na...
I really don't want to switch to Apple Music (it's not a great app either) but I'm really tired of dealing with playback issues due to the lack of buffered AirPlay 2 playback. If you try out a proper AirPlay 2 supporting app like Overcast or Apple Music, it's a dramatically better experience.
I also want nothing to do with Spotify's podcasts or audio books. And their macOS Chromium desktop app has also languished for years.
I'm entirely with you that even if I was a Spotify subscriber, I don't want their podcasts and audiobooks. In separate apps, optimized for use-case, covered by the same subscription, maybe. Forcing all those fundamentally different media formats through one UI and funnel is just wrong.
Apple homepod still does not support Spotify connect, nearly 7 years after it was launched.