I find the idea that nerds would ever chase off women particularly amusing. Hell, most of us would KILL to have women around. If women are electing to not pursue the field, it's certainly not because they're unwelcome. On every team that I've ever been on with women, the guys went out of their way to be nice to them.
I'm a programmer and IT expert. Regular 80ies computerkid (zx81, Sharp PC 1402, Basic, Peek & Poke, etc. growing up in parallel with microcomputers ... you know the drill). Computers and programming from there on out. I'm also quite good with women. A late bloomer. like most of us, I've gotten the hang of it in the last decade. I dance Tango and have had a measure of affairs since roughly the age of 35. And I enjoy the embrace of a cute women very much. It's also fun to learn how nerdy and insecure women themselves are! And sexually frustrated in just about the same amount as men! ... Only better at hiding it. :-) ... anyway:
I also run into female IT and Tech experts. Sadly not that often, for the known reasons, but occasionally I do. On at least two occasions I've caught myself being slightly disrespectful to women in tech, albeit with no bad intent. Once was explaing my tango partner - a women in her late 20ies on her way to a PHD in electronics - how I would use a dual-cinch-to-3,5mm jack audio adapter to hook a player to loudspeakers. Roughly 20 seconds in it dawned to me that, if anything, she would explain to me how to do it. I inmediately appologised and we resolved the awkward situation with some humor.
It was embarrasing none-the-less.
On another occasion I was basically explaining my smartphone in very simple terms to a female PHD in CS with expert Java knowledge - a team-lead. It was an Android phone. She'd actually just wanted to know which Android version it was running when she asked "What is that?". With a cliche computer guy or male web-hipster asking it, I might have caught the gist. The simple fact that she was quite young and good-looking had triggered male dominance behaviour in me and had me look like somewhat like a jerk. Again, I noticed it about 10 seconds in, but by then I'd already done it. She handled it very professionally, but I felt like a total douche. Still do actually, when thinking back.
You may think you're treating women respectfully while you're actually appearing quite condescending. Observe yourself if you get the chance - I've alway thought the same as you did, but since discovered some fine-tuning requirements in my behaviour towards women in our profession. QED.