Why? There were the reason why NVIDIA GPUs became so successful at the first place.
Who knows whether Jensen's current leadership isn't generating today's CUDA for NVIDIA?
The situation only exists because regulators in the 80s-20s believe that hardware should be a sanctioned monopoly. Intel, AMD, NVIDIA, Sun Microsystems, IBM, HP, and Microsoft were all involved. If it's not Jensen it'd be someone else, there is a good reason NVIDIA is called NVIDIA and not JENSEN. Jensen's leadership is as much resonsible for CUDA as G. W. Bush's.
More directly on topic, I can't help thinking this is also a question of "what have you done for me lately" versus "what are you going to do for me tomorrow". It's hard to doubt he and the company as a whole have executed a vision and reaped the rewards, but have they been planning and doing the groundwork for another act.
A nontrivial part of which is pumping up an infrastructure bubble with NVIDIA money. It wouldn't shock me if that very aggressive and increasingly questioned strategy plays a role in whatever happens to Jensen.
This well researched video I endorse. Sure Nvidia was touch and go a the very start but beyond that, they were just locked in.
How Nvidia Won Graphics Cards - Asianometry https://www.youtube.com/watch?v=TRZqE6H-dww