Oh come on.

The language means that if PSF at any point, maybe years from now, at some conference or wherever maybe somehow supports or hosts a panel about diversity and inclusion, the NSF can force them to pay the money back, even though it's already spent. That's not "wanting to discriminate", it's a free ticket for a rogue government to bully the PSF without a good argument, if it ever sees fit.

Even if I were an angry right wing DEI-hater I wouldn't accept the grant under these terms. If the government can just grab it back whatever under vague accusations, the money is just a liability.