The high tier companies told everyone before they stood on line that unless you have a minimum of 3.0, you were better off going somewhere else.
IIRC he was above average at Caltech, but GPA was abysmally low compared to applicants from Stanford, Harvard, Pomona, and other egregiously inflating schools.
From a distance, I think highly of Harvey Mudd, but I don't know their grading policies. I doubt they grade harder than Caltech, since HMC's branding is all about "we want to help you succeed" and Caltech is more of "we're going to beat you up [intellectually]."
However the graduation rate tells perhaps a (slightly) more nuanced story about rigor. HMC, despite beimg more expensive to attend than Caltech, had a lower 2023 graduation rate of 91.5% vs Caltech at 93.7%
it's not that different, and probably you can construct error bars that enclose both of these bounds within plausible parameters, but it suggests that there is a somewhat higher premium for failure of those actually accepted at HMC than even the mighty Caltech, and a greater willingness to uphold standards at the expense of angering (relatively) wealthy parents.