The overall GPA can still be used to rank, even at Harvard. The latin honors are fixed at top 5, 20, and 50 percent of graduating classes.

I don't really care about grade inflation overall because I don't think more competition for grades would improve Harvard as an educational institution.

I do think grading norms/curves may be important to standardize the distribution across majors. It's absolutely the case that some students avoid difficult courses. This is very unfortunate.