One of the many great things about children, if you're not a total heartless bastard of course, is that having them really sharpens your mind as to what's important and what's not. Most of these things the HN crowd obsesses over are shit, and the things that replace those things will also be shit, and the thing you make with those things--even if it makes you fabulously wealthy--will also be shit, and if you don't be…
So what you're saying is "you don't. People with children will not be as good". Great. That means I should not feel bad about any hypothetical statistics that show parents paid less than non-parents. You're saying parents are, on average, statistically, not as useful as non-parents to a company.
Frankly I think those of us who have been in the industry over 15 or 20 years know that adopting new technologies is not the hard or important part. Having the wisdom about how, when, and what to apply things, recognizing good engineering, and learning to work well in a team -- that's what's important.
Having kids might mean you can't stay up at night learning the latest JS framework -- but that very likely might be a good thing.