you convincing yourself that someone you don't like is generic =/= their music actually being generic
the rare times when rihanna has a generic song (ex: right now), she is dragged first and foremost by the navy. the reason you don't see her get criticized is because you're 1) not a stan and 2) she rarely has generic songs in the first place
if it was a common occurrence like it is for some of your faves, she would be rightfully dragged/criticized for it. but sane people don't criticize things that don't exist