Mainstream Rap.

Why has mainstream rap gone to shit? And has been filled with these prepubescent ******s yelling out "YOLO" and shit like that, and rappers with actual skill are either not getting known or are holding back their flow.
For example I used to completely HATE tyga until I heard this
https://www.youtube.com/watch?v=st_NctN3Hrc
Idc if that was prewritten, how the fuck does he manage to go from that to "rack city" I mean honestly, then you look at people like drake and lil wayne and wonder why the fuck they are famous, sure drake makes some alright music but overall it's just shit.
Opinions?
https://i49.tinypic.com/6f7a55.jpg