It actually doesn't, because NIST needs to speak to and be trusted by more than just a tiny clique. Djb crypto is widely known and used which means they have to deal with him whether they like it or not.
Cranks and assholes occasionally are unfairly treated, but generally are fairly ignored - the effort of dealing with their claims aren't worth it.
As an outsider, "respected cryptographer makes a narrow technical claim and is brushed off by NIST" and "sore loser that no-one talks to complains that people aren't entertaining his latest complaint about the ref" are very different situations, from which I will take very different actions.
This is looking more and more like the latter!