The guys with good chins who dont overly rely on that fact,can go far. Khabib's style is something you need a good chin for,even though his defensive abilities are amazing,much better than Cormier or Cain etc. But its an agressive come forward dominating style,and you will occasionaly eat hits to close the distance.
Without weight cutting he is near LHW limit. How do you think he would fare against range of JJ or Izzy. How explosive could he be with 90kg, how long would he last??? Praising his defensive ability is ok, but shaming Cain or DC while them being same height as Khabib is dick move. While Khabib was failing scale in LW they were facing great adversity in HW.