the longer a genre is around, the easier it is for people to fuck it up. major labels are more willing to sign anyone who can make a buck. some guys are the rap equivalent of britney spears.
but there's ALWAYS sick shit coming out. every year. always will be.
that's kind of a loaded statement. when people start to miss a certain era they'll look for its best qualities and try to reintegrate them. the 90s aren't "coming back" but they're definitely missed. hence elements of 90s music are returning, then they'll die out again and reappear.