No, it means that for families with AGI under @65k, which is above the median family income for a family of four, Princeton and I believe Harvard and Yale cover tuition, room and board.
And yes @ucbalumnus, there is a comprehensive cost that covers things other than tuition room and board. Given what I have seen from Princeton’s financial aid office, I would bet a billion dollars those costs can be waived as well for students with true need. Find me another set of schools with better aid.