Alcohol and drugs. Khabib said, when talking about Conor that, “Money doesn’t change you, it shows who you really are”. Nobody can tell him when he’s fucking up now, they’re too afraid of losing their meal ticket.
MMA has evolved and he hasn’t, the gym he’s at only produced one notable fighter, him. And it’s more due to his left hand than anything they taught him.
He needs to get off the drugs and alcohol, retire from MMA and fighting in general (professionally or otherwise) and just enjoy his wealth with his family.