Children will interrupt your career plans. If you want to have them, go for it, but understand that doing so will incur a penalty on your career timeline. You are choosing to spend time with your children instead of your career, and it really is not possible to have it all. Fortunately, childcare seems to be trending toward a more equitable split.
Which is why employers should equalize (and perhaps enforce) parental leave, so we don’t put mothers behind fathers.
And I agree that if someone chooses not to have any children at all, it’s very fair if their career ends up advancing a little faster due to not taking months/years off. I know that some disagree, but I don’t see how it can be any other way. I also believe it can be many times more meaningful than the career advancement delay to bring children into one’s family.
