I think you're talking absolute rubbish.
I would in no way have wanted my baby to be dragged out strapped in a car seat 3/4 times a day for school dropoffs and pickups. Neither did I want them traipsing round the post office or the supermarket during the time they were being minded. They had me and their dad for that.
Babies don't give a shite whether they are with other babies or a range of ages of children. My almost 2 year old was a nightmare to keep away from my new baby. Poor child spent a lot of time on the kitchen worktop to keep them out of reach!!!
A lot of a baby's day is spent sleeping and eating. Anyone can facilitate that. They aren't just cooped up as you seem to think. Mine were in beautiful bright airy rooms with a regularly changed range of toys, and a beautiful back garden with all manner of things to do. Unless the weather was awful they were out there every day, coats, hats etc on.
WTF does a baby need to "be out in the world"??? Parents do that!! What a load of utter tosh! And surely ALL of our children should be in "childproof rooms" or we are actually negligent!!
My children are adults as I have said. I can't tell between them and their friends who had a SAHP, who went to nursery, who had a childminder, who was "out in the world" (!!!), who was breastfed, who was not, who wasn't toilet trained until they were 11!
The consistency in the early years comes from the parents. Time in childcare is only a part of their life experience. Quite honestly, I don't believe my kids would have got to do the half of the stuff they did in nursery anywhere else, including at home. They were painting from when they were tiny. Mine all loved the beautiful toy kitchen and they had so many bits for it. I couldn't drag mine out some evenings, they were so absorbed. They had a lady come in every week to do singing and dancing with them. All sorts of age appropriate crafting. I don't remember the half of it.
Do you think a cm is doing that when her time is spent running about after other peoples' kids? TBF my last lady did when she had everyone picked up, but the other two absolutely didn't.