There are two concerns here.

First, that Spotify doesn't make clear when a track is produced by a Spotify "ghost artist".

And second, Spotify is in an unfair position as both the controller of the marketplace/platform, and as a participant on it. The allegation in this article is that Spotify are using their platform position to promote their own PFC program tracks over third party artists/labels.

To be clear, it's not necessarily consumers who are being harmed here. These tracks are supposedly targeted to cases where the consumer doesn't really care that much about the songs that are being played. Rather the party harmed are third party artists/labels who are competing for Spotify playlist space on an uneven playing field.