I mean that's not unusual either I suppose, it's a self promo strategy. Spotify does it themselves as well, mixing in relatively unknown artists into generated playlists to give them a bit more exposure which they would never get if "existing popularity" was the metric to include them in generated playlists. The article implies that artists can accept lower royalty payments to get more exposure like that too, so it's intentional by Spotify and the artists themselves. I mean personally I don't care for it, but good for them.

What I really don't like is the spam where they add a random well-known artist's name to their song to make it look like it's a collaboration, but it's either a low effort cover or has absolutely nothing to do with it. At least I've stopped gettring random basement mumble rap in generated metal playlists.