Let's not forget that Graham has also publicly written he would be loath to choose any woman as a startup founder "who had small children, or was likely to have them soon." The man has a type, and the demographics of YC reflect it.
I... would too? Startups take over your life, and so does taking care of young kids. Pretty hard to do both at the same time. Not impossible, but pretty hard, which is presumably why he said he’d be reluctant, not absolutely unwilling.
Leaving aside that there are driven people who work their asses off despite having young children, and that "startups consume your life" is the kind of belief VC have an interest in perpetuating, note that Graham in this statement is treating kids as a women's issue.
