I will say that kinda like when Pac said the rest of the country was more living a different lifestyle than The tri state and specifically NY.Nyc is a unique place you almost have to live in,know a lot of ppl from there,or visit a few times to try to get.
That uniqueness made hip hop,but at one point alienated others.
It's not that mid 90's rappers didn't sale,it's that Deathrow,Jimmy,Dre and Snoop raised the bar so much higher.
Record sales weren't the main focus of hip hop in general back then.Fans didn't care about 1st week sales and gold and platinum.
Also Interscope and Jimmy Iovine had a great system over there.Their machine is very powerful
36 Chambers sold a lot
Illmatic sold gold back then
Idk what Midnight Marauders sold but it's a great album.5 mics
Reasonable Doubt also did gold back then
Biggie sold in the mid 90's
The Fugees sold a whole bunch
Traditional hip hop for the most part has never been mainstream,but sometimes critical and commercial success meet and you get your Rakims,Fugees ,or OutKasts, or Eminems .