I have no inside knowledge of this case, but 2 thoughts for the anti mothers on the flightdeck brigade:
You complain about parents needing extra time to deal with their kids, whilst the heroic non-parents hold the fort. Have you ever thought who keeps the country going financially with their taxes after you retire - that's right, younger taxpayers. And where do they come from? So to complain that it is all pain and no gain for non-parents is not quite right.
Secondly, I know from personal experience that although planning how it is going to be after a child comes along is all very nice, the reality that bites can often be much different. You don't know in advance whether your child will sleep all night from a couple of months old, or wake up several times a night until they are 5 years old. Will they be good at amusing themselves so that you can get household stuff done as well as care for them at the times you are home? There are many other issues, but those 2 alone can make a huge difference.
Even parents whose partner isn't working can underestimate the impact of a kid, and how much time they soak up, so couples new to the game should get some slack if they didn't get the advance plan quite right.