I wonder if the same kind of thing is at play when I ask my Google Home Mini to play a song (on Spotify) and it plays a version by a cover band instead of the real thing, despite my stating the song and band name.

For example, I'll say: "OK Google, Play 'Hey Jude' by 'The Beatles'". Sometimes I'll get that song. But many others I'll get "Hey Jude" by a Beatles tribute band... I wouldn't be surprised if the version by the tribute band is cheaper to play.