Well yes. Hating a gender purely because they are that gender is sexist any way you slice it.
Say for example you had a bad history with men or have some traumatic event caused from a man or several men, it's still sexist to say you hate all men.
Yes it is still sexist
I hate when people say this, i understand that traumatic experiences hurt. All men are not the same we do not share one mind one personality one anything. so in all yes it is
Thanks for submitting!