Oh man is something I say to all sexes. Your comment just seems to be policing language with no point. This kinda stuff hurts your cause, which I wholly support.
The point is to avoid a situation where a (usually cis) person inadvertently invalidates a trans person's gender identity.
> This kinda stuff hurts your cause
So iiuc, what you're saying is, asking to use language that respects someone's gender identity hurts the cause of respecting people's gender identity.