The problem with these debates is that when people come out and make statements such as "well this study suggests x and y," it automatically leaves people feeling judged.
The reality here is that the increasing need for parents to return to work has created an industry which is there to look after the children of those parents, and there are inevitably going to be issues relating to this industry based on the fact that for the people who run the nurseries/childminders etc it is a job but the parents want to think of it as a loving environment because nobody wants to think of putting their child in a nursery where it is simply a fact of keeping someone in work and making money from other's need to work iyswim.
Ultimately parents need to do what works for them individually, because ultimately what works for one doesn't for another, and the reality is that most people only use childcare settings such as nurseries because they have to. And when they have to they feel the need to justify it by saying things like "oh but he just thrived there/needed the interactions with other children/needed things I couldn't provide," when actually what most of them are doing is needing their children to do well in these settings because these settings are rarely a choice but a necessity. And for the most part, these children do do well in whatever childcare setting they need to be in.
I vividly remember my next door neighbour saying "oh we're putting x into a nursery because he's just so advanced and sociable that he's going to need to be in group settings where he is constantly stimulated." He was eight weeks old at the time and he went into nursery from five months. Her justifications had nothing to do with her child and everything to do with her going back to work.
If we were just more accepting of the fact that people have to make their own life choices for their own reasons and spent less time judging individuals on both sides (be that going to work or staying at home) we could perhaps be in a better position to look at these childcare settings more objectively in terms of how they're run and what they could improve on, rather than emotionally in terms of "won't someone please think of the children."
Personally I think the fact that whenever people ask about childcare the amount of people who come on and say "look for a good one but it means you'll have to do a lot of looking around, speaks volumes. Because what that tells us is that childcare settings in the UK are inadequate for the most part, and that has to do with the setting not the parents' need to seek childcare. The fact that so many parents do need to seek childcare means that a huge amount of people have found a way to exploit that by setting up nurseries/childminding facilities and they operate to the lowest possible standards at the highest possible prices.
Fact is that we are now a generation where parents need to work. So rather than questioning which setting is better for children psychologically, we need to start questioning what facilities a setting is providing in order to facilitate the best possible childcare that parents have no option but to pay for.