The gender pronoun wasn't actually relevant but thanks for doing research!
Georgieporgie is tired of working with 25 - 35 year old man children. How is that hating all men or generalizing to all men? In fact he specifically said "working with" as in he actually worked with these people.
You seem awfully sensitive.
He can't possibly have experience with ALL males of 25 - 35 in the industry. Making such a general statement can be perceived as misandry.
EDIT: My reaction was similar to how some people react to "I'm seriously considering leaving the field of software because I'm tired of working with 25 - 35 year old immature bitches/sluts ."
I will consider the comment on reading comprehension and sensitivity.