Interesting piece. The point about gender differences in attitudes to men and women taking time out for kids is well-taken, but I think the 'extra effort' coping with colleagues' hangovers and cake-related counselling, for instance, is overplayed.
Having worked in a group with several women all working part-time, there was never, ever any flexibility on their part about hours (understandably; as the author points out there is very little time to rush back before the nanny departs) and lots of instances of extra time having been taken during the day when kids were ill, sports days, nativity plays, parent-teacher stuff etc.
Add that to the part-time working and I'm afraid that childless people were always covering for the part-timers, both at either end of their fixed hour days and during their days off, something which I can't remember being reciprocated on a single occasion.
Interestingly, when my own (exploratory) request to go part-time was heard, it was deemed to not be in the interests of the business, because there were already too many part-timers...
'Respect for life choices' is one thing, but when there is no reciprocation, no respect for one's own life choices, it's quite a tough ask. Having kids is, after all, a choice, one which is accompanied not only by the manifold joys of having children, but also via the tax and benefits system.
You might say - not without some justification - that the 'system' is already stacked in favour of people without kids in terms of promotion, but surely creating a 'level' playing field removes the choice advantages of not having kids, and therefore amounts to positive discrimination.
The author's example of the female board member is interesting. Fixed hours, part-time, no meetings during school hols: sounds more like Inflexible working...