And this right here is the problem. It makes you lazy, it makes music discovery a passive process. It kills your soul. By requiring active effort to engage with a scene and music itself, you regain a certain beauty and excitement to music because it becomes an interactive process and something you are part of. Once you have "earned" a new album and or band by discovering it on your own whims, you are more motivated to share it and discuss it with people as opposed to just appreciating it as an individual.
Sure, there's a time and a place where you do just want to kick on a vibe and do something else (especially at work) and for that AM Stations or Spotify Radio is adequate, however, it is a gilded cage.
You have to understand that this reads like gatekeeping nonsense to a lot of people.
But what you describe takes work and Spotify radio and similar features from their competitors don't.
As someone who also built up a big library during the golden ages of music piracy, the primary benefit of the Spotify-like services is not their libraries. It is that they remove the need to do the work in both music selection and discovery. They provide a middle ground between just random music selection and entirely intentional selection. Sometimes I just want a specific musical vibe without having to design a playlist or choose a specific singular artist. In addition these services are smart enough to understand that vibe and mix new music in that fits that vibe which I therefore might also enjoy.
Is there anything that can adequately replicate this type of radio style listening while using one's own library that doesn't require them to spend hours and hours both proactively seeking out new music and meticulously updating their library's metadata using something like Musicbrainz (or whatever the modern equivalent now is)?