Jeezy has never really been super commercially huge, he's generally for street rap purists, he's like michael jackson in mad hoods and shyt like that. He's not on twitter, dropping ustreams, on twitter spamming or posting mad videos to YN showing his lavish lifestyle and all that shyt.
He goes city to city, club to club, venue to venue and therefore his buzz might not be felt by the people not really checking for him. While Ross's hype is bigger than his actual buzz. The complete opposite of Jeezy. Jeezy can drop a strip club joint with Plies and it hits
#30 like nothing.
So while Ross has been a lot bigger commercially, he's not been a lot bigger overall. They sell out the same venues, jeezy sells more and his singles chart higher in Jeezys worst period career wise. Ross even got MTV to claim that he was hotter than Kanye, Wayne and Drake. As far as music goes though, even though GFID was a let down he's probably been top 3 since 2009.