This is a huge cut. Back of the envelope calculations for UCLA (a big research university with public finance information): $200M cut in operating revenue.
In 2023, UCLA had $270M in indirect costs [1] and they negotiated a rate of 57% with the NIH [2]. So, they had about $473M in direct costs. The new rate would be 15%, which is ~$71M. $270M-$71M = $200M.