Um, in my experience, straight guys are only comfortable with admitting they like Rihanna. For the mostpart, they are embrassed as hell and are closet stans of the pop gurls (my closest friend like Katy Perry but would kill me if I told anyone).
But yeah, the stigma wasn't so bad in the eighties and ninties when gay culture wasn't as abundant and abbrasive as it is now. Madonna was loved by many straight men until the association with homosexuality made them embrassed to like her.
I dont know any straight guys that STAN for pop girls. But a few straight guys "like" Rihanna and thats mostly due to Run this Town, Live Your life, and Pour it up