The primary meaning of "man" is "male human." The secondary meaning is "human." However, that means it is possible to refer to a group of women as "men." Or a group that is predominantly women, because I would hope that no one would be quite stupid enough to use "men" to refer to an exclusively female group. However, throw in a single male, and the female nature of the group is overwhelmed. The women no longer count, and it's a group of men. As opposed to being something different--a group of people. We have multiple words which mean "a group of Homo sapiens of both male and female," so why continue to use one which means "male Homo sapiens except when it's both male and female"? Come to that, why aren't more men upset at it? And why is it that we're able to limit words that other groups find offensive, but it's hardest to limit words that women find offensive?
You should know that I refer to myself as "legally crazy." I am not legally insane, but I am seriously mentally ill enough so that the Social Security Administration considers me too disabled to hold a job for six months. That's too long to say. I think "crazy" is a perfectly acceptable term provided the attitude behind it isn't insulting. The word is not the most important part, but I think the word should meet the attitude halfway.
"Now everyone was giving her that kind of look UFOlogists get when they suddenly say, 'Hey, if you shade your eyes you can see it is just a flock of geese after all.'"
"You can't erase icing."
"I can't believe it doesn't work! I found it on the internet, man!"