Is there a reason why trans people (specifically trans men, since trans people of other genders would qualify under the "gender" criterion) are not included in the URM criteria? It seems kinda odd to include all these other minority groups but not trans people. Are transgender people not actually underrepresented at ICLR?

While what you are saying here is true, it doesn't really apply in this case because Anima Anandkumar is a famous researcher.