Buffy, I struggle with the "I wonder whether the idea that it requires a total change in a mother's life has to be everyone's reality". Not with the wondering, but where it would lead in a capitalist world. The tone kind of reminds me of the "blue sky thinking" you hear in the workplace that usually leads to about a third of your team getting sacked. "So where is it written that we actually need a whole separate contracts admin team?" you know the sort of thing.
It depends on changing from what. I would happily take a no-longer-quite-newborn baby on my back into certain kinds of work situation (chatty, informal, I know everyone reasonably well, not too intellectually demanding, a certain amount of routine work done with the hands, no strict timetabling that will stop me pottering off to change a nappy or stopping to bf when needed) but not others (negotiating something tough, designing something, creating systems, working to tight deadlines, doing things in real time which are irrevocable should I want to change them later). It's a long time since I was at university but that second group of things looks a lot like what university used to be like.
And I think it should be. I think people at university should be able to work to the best of their intellectual ability, not just show up and mean well and put the hours in.
I am a feminist and I think that looking after a newborn baby is bloody hard work. I welcome the idea that I don't have to do that and much else, for a little while.
I find babies knackering. I am introvert, and a baby is another person, and having that demand on me all the time is a significant drain on my mental and emotional resources. Some people are all "the more the merrier" about every situation - and if they are studying to their personality are perhaps learning in a subject where it is entirely appropriate to consider it part of the eventual job to be organised and cheerful while people are making constant small and large demands on you from all directions.
Actual academic study in its traditional sense is something entirely different. Being unable to do theoretical physics while someone is even looking at you quizzically wondering if that chair is taken, is not making you unsuitable to be a theoretical physicist. (I am that kind of person.) I kind of think it is fine to have enclaves where people only have to do their goddamned subject. All the people in the class that is. And don't have to juggle emotional and social needs of others at the same time.
Your student in a wheelchair, your student with Tourettes, your student with a long term illness are still individual single human beings who ultimately are well organised and considerate people who don't infict emotional neediness on those around them. Bringing a baby into the mix is bringing a great big ball of needy. They are exhausting.