Sorry, only read the first and last few pages so hope I'm not going over old ground.
I think the article isn't about the way women talk to one another - it's about the patriarchal set up of society - the way advertising and the media portrays motherhood (her sliding scale). I don't think she is meaning that women sneer at other women - just maybe she is saying that some women have adopted the stance without as much thought as maybe it should have.
I agree with the article that there is a lot out there that lauds motherhood over fatherhood (or parenthood) and transforms a woman's role in society as soon as she has a child in a way that isn't the case for men. I think she is talking about the pervasive mother worship that enables men to say that they would love to be more involved with their kids - without ever having to make the lifestyle changes women do as parents.
You just don't hear 'fatherhood is the most important job in the world' because no one considers fatherhood to be a 'job' as in a replacement career. This drives the low low rates of stay at home fathers. And as for the idea of 'full time mum' - does that make all working fathers 'part time'? This is exactly the problem.
And sorry MillyMollyMax but I wonder what the average hourly rate of pay is for those little businesses? I see too many SAHM with these little businesses that I reckon may just about break even - but more often than not lose money and certainly wouldn't be a going concern if they had to bring in a meaningful income. They are hobbies. Not always, but mostly.