It is because they don't want to be there. The opportunity is there for everyone to take thus men and women. I actually think women have an advantage in this space and it is up to them to see it and advantage of it.
As a woman, I am tired this. If you want it, go and get it. There shouldn't be any special treatment. Prove you deserve to be at the table, prove you deserve to be there based merits etc.. Not because of gender, race etc.
People are going to wonder why this conclusion? Because when people see you as a women trying to achieve something, a lot are willing to help and push you. Don't moan about it, go ahead and just get into Tech if you want it that bad.