Many of the very best have a different grade approach

Why is it that many of the very best climbers like Ondra, Webb, Graham and Ceria, either are the ones who use personal grades most frequently, have a very broad grade pyramid, or, like Sharma and Mego, simply do not seem care about grades? Could it be that the ones who are driven by the grades instead of focusing more on the pure climbing challenges, have hard time to pass the 9a and 8B+ barrier? Maybe this relates to the fact that grade thoughts create anxiety, which makes it harder to send. If you climb because you enjoy the challenge and get pleased even if you fail or do easier climbs you might have more positive energy instead of being pushed by your grand focus on the grade.