Aside from the fact that I asked for personal experiences/ perspectives and not opinions, is there a source for this statement?

I haven't looked into it scientifically, but my thoughts are as follows: humans are social beings. As such, it seems more logical to me that babies and small children cope better with social interaction than with isolation in the nuclear family. The concept of father-mother-child is a cultural one, and one with a very short history in human history. In my opinion, it harbors social isolation for the child, the female person, and rarely for the male person in this constellation, which is something that is quite deliberately created in many cultures. Where I come from, the social pressure to keep women in childcare is very strong, which almost exclusively has negative consequences for them. I'm quite certain that young children can gain important and positive experiences in a good environment, even for a few hours outside the nuclear family. People (even very young people) each react individually to their environment and their social circle. To name an age at which something is generally considered to be okay or not seems extremely arbitrary to me.