It’s been a decade at least since I heavily used Pandora but I remember it being even worse than Spotify at this. The algorithm seemed to latch on to one or two tracks from any given artist and they’d continue popping up no matter how I trained it. Great as a discovery tool for artists I guess, but as endless radio Spotify does a way better job at least trying to reach into back catalogs and including more than one or two songs. There’s still a lot of room for improvement, and it does seem to get hung up in similar ways.
Maybe Pandora has improved since.