I really love how Khabib is a sportsman. He views the belt as a reflection of the best fighter in the division and he only wants to fight the best fighter available for the belt. Proving he is the best is more important than the belt to him.
Same reason he wants to fight GSP. It’s not for the money, it’s not for the spectacle. He respects GSP, regards him as the best and wants to test himself against the best.