It is impossible to remain as hungry as 8 years ago.
He won the Pride GP, he won the UFC belt, he is already considered a legend and he is only 31 years old. He has had epic wars, he is one of the most beloved fighters.
After all those things it is not that easy to remain focused and motivated.
Plus he has had surgeries and that is a huge factor.
IMO he looked OK in the Vera fight. In the Hendo fight, he was destroyed during the first 3 rounds, and then he destroyed Hendo during the last 2 rounds.
The Jones fight is the only one where he looked terrible.