Harvard’s net price calculator indicates that a maximum-financial-aid US student sees a net price of $4,600.
https://college.harvard.edu/financial-aid/net-price-calculator
While the difference between $4,600 and “free of charge” is probably trivial to the forum posters here who complain about not getting any financial aid because their incomes are too high, it is not trivial to most of those who would actually get maximum financial aid at Harvard.