Since we had numerous activities with other new parents (from Facebook groups; local mommy meet-ups at the mommy café; sports courses before and after pregnancy, where you also meet privately, talk, etc.), I can tell you that here, in the absolutely most child-friendly neighborhood in the city, the norm is that children are placed in daycare or with a daycare mother by about one year old at the latest. Our 1 1/2 years was definitely the absolute exception. And my wife is also glad because being there for the little one every second from early to late is exhausting.
With the daycare mother, she plays in the sandbox with other children in the mornings. Even if no cliques form or anything like that, she already interacts with other children. They exchange toys, fill molds together in the sandbox, or chase each other a bit. I have also read that "real" social interaction comes later, but at 1 1/2 years old, it is not the case that every child plays alone, definitely not.
There was once a book about children and upbringing among indigenous people, and there it was described that children were definitely not with their mother all day. They were often carried, yes. But also by other female caregivers like the grandmother, the older sister, or other women from the village/tribe.
If someone wants to stay at home until 3 years old, they are welcome to do so. But it is by no means the norm. The norm is daycare/daycare mother at about one year old. That does not mean you do not see your children during the week. Our daughter will then be picked up 2-3 times a week directly after her nap and 2-3 times a week around 4:00 or 4:30 p.m. She definitely does not go to bed before 8:00 p.m.; that would lead to relentless rebellion and definitely no sleep. So we have at least 4 hours per day with her after work or longer and, of course, the entire weekend. I do not think that is little or too little.