Im not entirely sure he has been on drugs during press conferences etc. although he did seem excitable and restless at the Khabib conference but it couldve been a mix of the magnitude of his opponent, knowing it wouldnt be easy to "get in his head" and some whiskey shots
That being said there isn't a doubt in my mind McGregor takes drugs and Im sure his time off after the Mayweather fight wasn't full of two a days and green juices
Imo Conors performance against Khabib was disappointing even thought I dont think he didnt train enough, I think that the problem was he trained too much. After his time off which sporadic training, partying, travelling and fatherhood then jumped straight into a camp that was brutal and a war to prepare for Khabib and overtrained himself hence the total lack of sharpness