Citation needed.

Looking at Form 990 for several top private research universities:

Harvard: $1,462M tuition vs $592M government grant

Yale: $680M tuition vs $528M government grant

Princeton: $369M tuition vs $293M government grant

Stanford: $938M tuition vs $1,299M government grant

As you go down in research activity, the differences only get bigger.

Rochester Institute of Technology: $501m tuition vs $113m government grant

University of New Haven: $214m tuition vs $6m government grant

U.S. taxpayers are not paying for foreign students. Foreign students are paying for themselves, and then some.