I heard a similar story a couple of years ago: some no-name artist with a fairly good amount of plays on Spotify who could not be found anywhere else online. It was less obviously ai-generated back then (more instrumental than vibe/ambient), so it was speculated that it could be a musician working on commission for Spotify, who was then stuffing their playlists with these songs to cut costs. I can't find any traces of this story anymore though.