This is a strawman.
1. Female youtubers are not who we are talking about. If they have a problem, they have a problem. But I doubt it involved explain why being a woman makes one incapable of being a Ghostbuster.
2. Why would a mix be better then an all female team?
3. As one who had problems with them rebooting Ghosbusters, one of my favorite things growing up, I have never felt the need to attack this film as a gimmick because they cast women. McKinnon and Jones don't exactly look funny to me in the trailer, but I haven't needed to dump vitriol on them. When you react impulsively, spew hate in the way many have done her, it makes things apparent.
When grown men react like children, it reveals a lot. I know, I have done it. One can dislike them rebooting Ghostbusters, but that doesn't mean suddenly one isn't sexist in how they have approached this film.
That anyone cries about feminism being brought into this or women seeing this as a sign of progress for them, is showing themselves. As a man, I don't know what it is like. I didn't grow up having to try and find action figures like me. They were there.