No, of course the Hertz winner did not have a 3.5 GPA in a school where the average GPA was 3.6. He had a 4.0, a large number of AP courses, and many university-level courses beyond AP, with a broad distribution of topics. His GPA and test scores were as high as they could possibly be.
I am writing about two different circumstances, which seem to have become conflated. (Probably my fault for not being clear enough initially.)
The commonality is that the local high school had a ton of work, much of it busywork that did not enhance learning.
It has been suggested in the past that students should just blow off the busywork (lots of boys do, at least elsewhere) and settle for a B, which is perfectly fine. This would allow them to get the amount of sleep they need and also to pursue their own interests. In many regards, this would be better. Just estimating, but I think this strategy would yield a 3.4-3.5, and the student would wind up in the bottom half of the class. That does somewhat restrict college choices.
My other comment about the workload is that students who decided to negotiate it, with non-zero attendant sacrifices, might be more likely to feel that if they had intellectual qualifications that were genuinely top-rate: brilliance, academic skills, creativity, insight, curiosity, and if they had good personal qualities (helpfulness, generosity, concern for others), plus the desire to attend a “top” school, they ought to be able to get in. Perhaps the students did not think so. Their parents surely did, though! :). It is often said that there is just not enough room for all of the incredibly impressive students who apply to “top” schools. That depends on where you draw the line for “incredibly impressive.” Where I draw it, there is room.
With regard to MIT being a “pressure cooker,” there is no sign of that in Feynman’s anecdotal writing about his time at MIT. At some currently unknown point below Feynman’s level of genius, it does become a pressure cooker, presumably.