More oft-repeated poppycock. Firstly, by 1983 rap had already splintered into a handful of sub-genres which could exist symbiotically. Secondly, rather than making a whole generation of rappers irrelevant, it provoked the Furious Five and the Coldcrush Brothers into recording their best studio songs as groups: Step Off and Fresh, Fly, Wild, And Bold, the former being a top 10 pop hit across Europe. Thirdly, Melle Mel, Kool Moe Dee, and Spoonie Gee all had their biggest hits post-Sucker MC's: Beat Street Breakdown, I Feel For You, How Ya Like Me Now, Wild Wild West, and The Godfather.
This ain't to say that Sucker MC's wasn't a game changer, but its impact has been vastly exaggerated by those glib critics who want to spin the story of 80s rap in neat 'n' tidy generational shifts and grand Slay Thy Father gestures. Anyone caught propagating this horseshit from this point forth should be forced to review Rev Run's appalling 2005 solo album Distortion for the rest of eternity once they depart this spinning chunk of granite and water. Raise Hell on that thought, suckers.