"The only real sexism prevalent in the tech industry are the groups of militant feminists setting up endless, patronizing, segregated "coding for girls" meetups."
It's easy for this kind of thing to be completely invisible when this is your attitude. Sexism in the tech industry is alive and well, and there are a lot of good reasons to have meet-ups for both girls and women.
When you immediately start lashing out about "militant feminists" the second someone suggests that sexism exists, you're saying that our experiences are invalid and that you know better than us how welcome we are in the industry. It should be completely unsurprising that this does not make us feel welcome.