Well Froch-Grocves was a complete megafight and Groves had never held anything more than a Commonwealth title.
I think our definitions of a megafight are different. Can't really say one is wrong and one is right I guess. Stevenson-Kovalev would be a megafight. Mayweather-Canelo was. Calzaghe-Kessler. Cotto-Margarito. Fights of that ilk.
Kovalev snatches Pascal and Stevenson's career continues to go down the toilet. By the time he's ready to fight Kovalev, Kovalev's team will deserve 75% of the purse compared to the declining fanbase of the super ducker.
Imploding is a strong term. Sukhotsky isnt a terrible fighter, but hes(Stevenson) definitely being massively overshadowed by Kovalev now.