It's not evil. It's not mean-spirited. It is a tad sexist, but not in a super offensive way. Probably the worst thing about it is that it's turning away some women and some feminist men. I doubt Gun.io intended that.

I think it's a good example of an easy thing to change for the tech community to be more inviting to women. If we want to break down stereotypes and gender ratios in tech, one thing we can do is make it more inviting for women to work here.