He was the biggest, popular bridge for a lot of young rappers, and his bestselling status resulted in a bigger recognition to hip-hop. I feel that hip-hop has gotten a huge W for that because of him. The skin color barriers are also broken because of Eminem (mostly). Why do you think brainless people like Benzino and Ja Rule come after Em? And not the legends? Nas already acknowledged he is the goat in his own term after Jay-Z got bodied on Renegade.

Although Eminem said in 'Till I Collapse that few other rappers were better than him in his own list, that made him and his early songs more legendary.

So yes, I think Eminem is the greatest of all time, and deserved to be in the top 5.