Does he? He doesn't seem especially greedy to me, given the competition, and the interviews he's had about how he thinks about his employees (I was one of them).
You're speaking as if Jensen is the only one dragging Nvidia on his shoulders. Nvidia will always have its employees push to make more money, that's the entire point of a company. Jensen has made enough to last several generations but his wealth is tied to Nvidia stock massively. It would be different if he was the only one getting rich off Nvidia which is not true at all.