He's probably not the goat of CSGO. I wouldn't say anybody is but he has definitely been dominant. Half 2014, whole 2015 and first few months in 2016 before the injury he was easily the best player in the world. Together with GuardiaN.
Coldzera is the best in terms of overall accomplishments and consistent individual performances... followed closely by Flusha and GTR.
But S1mple is probably the best in terms of raw skill... followed closely by Shox and F0rest.