My music library is hosted on my server, automatically synced locally on fixed devices and played from local files most of the time. Streaming services combine the advantage of sometimes disappearing, altering, removing content with the other advantage of needing an active internet connection at all time. That’s neither a good thing nor an efficient thing when the alternative is cheap and works all the time from everywhere.
Of course, I know this is not the most common use case; most people usually don’t care about any of this (and usually complain when something break). But it exists.
“Freeing up memory and eliminating unused apps and files” sounds like the kind of bullshit app we have on Android already. Why bring that to PC.