It's really a frivolous debate, if you can make a logical argument why any of the guys I named shouldn't be listed ahead P4P by all means go ahead.
Kovalev, Klitsckho, Crawford, Gonzalaz, Estrada, Ward, Alvarez, Cotto, Uchiyama, Walters, Rignodeaux,Pacquiao, Bradley, ect all skill, dominant...
He's kinda right though, I can name 10 skilled dominate fighter that deserve a P4P ranking than GGG.
It's all opinion really until proven otherwise, me personally from watching both relative to their comp I rate Canelo higher. Stylewise I think...