As you noted, things were a lot different in America. I cannot speak with authority about the situation in the UK, only from personal recollection however.

There is a definite bond formed when the mother is able to spend time with the baby, including breast feeding, instead of handing off that role to a Grandparent or Nanny.

I believe society develops taboos about certain parts of the human body. They range from one extreme of the burka to nudism. I guess if women could walk around topless like men do on hot days it would certainly change stereotypical opinion.