Foxcub, I liked your earlier point about the ideal of a mother at home alone with her baby being an idealised concept, emanating from the 50s.
Even in today's nuclear family, where the mother is an SAHM, it is likely that she has more than one child, of different ages. This one-to-one gazing into your baby's eyes with dyadic intensity only applies to the first. The reality is mother dragging baby on school run, or trying to cook a meal with pre-schooler at her skirts and baby crawling off somewhere, laundry waiting to be hung up, postman at the door.
I have always taken 1 year's maternity leave, and the amount of attention the second got certainly fell off dramatically. Now if I had 3 ....
Whereas, with my dcs at nursery, the carers are 100% there for the children. They have activities. They have nicely planned meals. If one child is crying, a carer goes to them immediately. The nursery my dcs go to are biggish, there is always an extra pair of hands to help, with more staff drafted in at mealtimes. As far as I can see, the children were happy and occupied and if they needed attention, were given it.
I know this because I spend time in the rooms, whilst settling them in. I come and go as I please, the staff don't mind. What I see is the reality of life there - it is not a show they put up for me. And they take their child-to-staff ratios very seriously (it is all regulated by Ofsted anyway). They were large happy chaotic rooms of children and staff. I was always happy to leave my dcs there and they settled quickly.
My children have always gone in to nursery from 1. As have a lot of their friends. I have yet to see any "emotional damage". On the contrary, the children thrive there. They are polite and friendly.
I dare say my second child got more attention at nursery than he got from me as his mother at home, busy with chores and the school run!