Saying this a Golden era is just Charlmagne talkin, but there is no question the quality of hip hop is on an upswing. That said, the reason why rap sounds so good now, is because it creatively and artistically bottomed out in 2006-2009.
If you wife up and fck a fat, nasty, smelly bytch for 3 years, and you drop her for some solid puss, that next chick gunna feel like Halle Berry in her prime to you. Rap fans were abused with that snap bullsht.
Really, this era begins and ends with Kendrick. There are some dope artists now, dont get me wrong, but Kendrick is the best MC to come along in 20 years since Nasir Jones.