I posted two freestyles that Melle Mel did with Grandmaster Flash on the turntables. If you listen to what they're doing it's not the same thing that Kendrick, J Cole, Big Krit, Future, Wale, or Drake is doing.
First of all it sounds like an off the top of the dome freestyle. And he's rapping with a DJ mixing records. Ask yourself when's the last time you heard Kanye West, Scarface, Busta Rhymes, Jay Z, or Nas rap with a DJ juggling beats?
Anyway, Melle Mel is the first Hip Hop MC. There's a website called Thafoundation.com that is owned and operated by a brother named Troy L Smith. He has hundreds of tapes from the old school era (78-84) On the website he interviews old school MCs and DJs. When asked; who was the first person you ever saw rap over a beat while the DJ is juggling two copies of the same record? Melle Mel's name comes up more than anybody else.
If you listen to the songs in the O/P and the freestyles I posted and the story that I just told, you can make an argument for Melle Mel being the GOAT.