Re: You want Equality? You get Equality.
Quite a lot of men do more than 50% of the child care, especially in cases where the woman is the breadwinner (my brother is in exactly that situation, as was my godmother's family, and quite a few other I know).
What you're essentially saying is that because a majority of men don't do this, then nobody should judge things on a case by case basis, which is complete bollocks.
The most common distribution of families is to have a primary breadwinner, and now it's pretty much necessary to have a second income due to housing costs (which only rose because people started having second incomes to afford the nice houses, so the market rapidly adapted).
Your statement says that there should be no nuance. If the woman is a breadwinner, and has a partner who is the second income, she should still have all the benefits of being that second income (i.e. at whim access to family and the ability to not meet the standard to which an arbitrary neutral person would be held to). If the breadwinner is a man, then they do not get recourse to this.
It really is that simple. Men, by and large, sacrifice family time to work and provide. The really successful women I know also follow that model; they've sacrificed quite a bit of family time in order to hold down the top jobs (which they can do marvellously).
Some have chosen to step back from the high powered roles in order to have the family time they desire, even if they've been a primary breadwinner. They just get by on lesser pay and a lower rated job, where the hours and calls fit what life flexibililty they way.
Saying "Group B is more affected than Group A, because group B chooses to do something a particular way" is discriminatory in itself.