The main problem

> This license can be seen as discriminating against a class of potential licensees [...] who might seek to bring claims enforcing their rights against the releaser

In the context of OSD, "discrimination" is usually understood to mean *explicit* discrimination, like "this software shall not be used by the military," or "this software shall not be used by citizens of [some country]." I'm not certain that disparate impact can never be the basis of an OSD 5 or 6 problem, but neither am I convinced that is such an exception.

We can't make a blanket exception for all disparate impacts, because then the exception swallows the rule, and we get absurd results like (e.g.) GPLv3 "discriminates against" Apple. So there needs to be some kind of line between acceptable disparate impacts, and unacceptable impacts, but I don't see where that line should be drawn, nor why this license in particular goes too far.

Disclosure: I work for Google (which likely has relevant policy preferences here). The opinions above are my own (and I don't speak for anyone else).