I read that differently. There are harder problems in NP, in the same way there are 7ft tall people in the set of people over 6ft tall. So ‘at least NP hard’ I understood as ‘in NP but maybe in a subset of NP that is harder’.

I meant to say that it being NP hard was the beginning of issues. Even if there was a polynomial time algorithm for it there are other can of worms to deal with.

But I was wrong ultimately