Most conversations do not require any information about a person's identity, so every idea stands on it's own merit.
The perceived hostility emerges when a person tries to support their viewpoint by irrelevant factors (gender, sexual orientation, race, etc.).
It's the equivalent of walking into an anonymous alcoholics meeting with booze, telling everyone how great it is to drink.
There is no reason for them to cater to you, therefore they want to get rid of you in a fast or fun way. Hostility can be both funny and gets rid of people who do not fit in.
(Warning: VERY harsh language)
>If I can pontificate a bit for your edification, one of the rules of the internet is "There are no girls on the internet". This rule does not mean what you think it means.
>In real life, people like you for being a girl. They want to fuck you, so they pay attention to you and pretend what you have to say is interesting, or that you are smart and clever. On the internet, we don't get a chance to fuck you. This means the advantage of being a "girl" does not exist. You don't get a bonus in a conversation just because I'd like to put my cock in you.
>When you make a stupid post like "hurr durr i'm a gurl" you are begging for attention. The only reason to post it is because you want your girl advantage back, because you are too vapid and stupid to do or say anything interesting without it. You are forgetting the rules, there are no girls on the internet.