The problem I have is mainly with the fable and mysticism of Khabib which is similar to Fedor heavily imo.
But, he is legit an all-time great, etc. With that said, Khabib never went up a weight class. Sure he doesn't have to or anything, but for the relevance of this conversation he would be to fight GSP.
I think at 170 Khabib gets killed by GSP even now.
In fact I don't think Khabib's game would work at 170, I just think he's not big or strong enough to do it there. That 15lb jump is huge and I think guys like Covington would beat him, Usman obviously. So I think in context GSP going up to 185 once to fight the champion, who all agree was a "weak" champ in Bisping...he still struggled albeit off a 4 year layoff or something.
McGregor also fought Khabib up a weight class at 155 for the record, as did Porier but he was more cemented as a LW by then. I just think, and this should be obvious to anyone not delusional roleplaying as part of Khabib's team, that a lot of his success comes from strength and size. On top of that he's the best wrestler/grappler LW has ever seen in the UFC/MMA. I just don't think that translates to WW, and GSP isn't fighting him at 155, 165 would be the lowest possible class. I just don't see Khabib ever beating GSP, horrible matchup for him.
Maybe Khabib would put on size if he ever moved up to 170. I mean Khabib is not that short for a WW compared to Usman, Woodley