Is because he's never faced adversity or a loss. He dominates all his opponents and that's the reason why. The reasons the other guys get the praise in addition other stuff(# of title defenses, sos etc) is they have faced adversity and shown they can won in multiple ways. Khabib hasn't shown that It's kinda crazy to suggest but had khabib lost to barboza or something than go on to beat barboza in a rematch, Conor, gaethje, Dustin. The media would spin it at omg, look how much he's grown as a fighter. Etc there are still fighters and journalists that say khabibs striking isn't effective. I think the fight world see khabib as a one trick pony(Kevin holland for sure has called him that) and believe eventually he won't be able to win his way. So they're banking on that. Khabib could finish 35-0 at lw and the goalpost will move to he didn't go to ww in the era of double champs Tl; Dr khabibs never been through adversity or lost his dominant style is held against him because he hasn't shown to win multiple ways.