This is difficult to be objective with, since there is going to be a bias towards our personal preferences. I manage some record stores and worked in some others so I hear people debate this shit daily, sometimes talking over me while I try to usher them the fuck out of the store. If we're going to be petty would you count "post MJ" after his output ceased or after he died? A handful of years isn't a lot to show lasting importance or I'd just say reluctantly Lady Gaga.
She at least has been seen with G.I.S.M and Doom patches, points for that.
If it's post MJ's major contributions to pop culture sans kid fucking jokes the impact probably has been most felt by Nirvana. Bands like The Black Keys etc, while probably talking about 1970's garage rock as influences, wouldn't be as palatable to a lot of audiences if it weren't for Nirvana's breaking through in the 90's. Also helped a lot of people dig deep into the indie and punk scenes, sort of how coffee can gateway to coke. Sort of. Can we use meth as a metaphor for people with shitty taste?