I think this comment thread is a pretty good illustration of the problem. A group of women are saying, "hey, we think this is a beneficial project, for this reason and this other reason," and a bunch of men are saying "WRONG it's pretty much white supremacy except against men." Forums reflect their membership -- in an industry dominated by men, discussions will be slanted away from positions held by women unless compensatory measures are taken.
Men don't need it - in technology and many other industry spaces, we are comfortable voicing our experiences because we know they'll be well-received and affirmed by much of our audience. We're the prevailing voice in the broad group, so we're already being heard.
If you're creating a space for men only, it's either because you're part of another group with a sidelined voice (e.g. gay men) or because you have Damore-esque ideas about the world and really do want to be exclusive.