It seems that, in all of Asia, the Mediterranean nations of Europe and, probably in old Europe, it is the extended family which has surrounded and sustained a growing child. I know nothing about family life in other parts of the world. That 3 generations could live together, with mutual support, appears to me to be quite reasonable, and to be respected. Some exploitation and/or abuse will, no doubt, occur; but cannot be assumed to be endemic by those who have no relevant experience.
In such societies, the old do not have to live alone, unless they chose to. In addition, the extended family is generally surrounded by, and socialises with, relatives. The exceptions to this pattern of communal life may occur in the early stages of migration.
I grew up in Asia in an immigrant family. While I obviously cannot remember how I was brought up as an infant, I observed how my sisters and cousins were cuddled, petted, massaged with oil daily, and held in the arms of visitors. Often the babies would fall asleep in their arms. I believe that babies so treated grew up feeling protected and confident. Yet, as we grew older, there was no more of that pampering, resulting in, I believe, a certain attitude of self-sufficiency and independence.
Through chain migration, my nuclear family was supported by a continuity of cultural traditions. Eventually, extended families would evolve in this community. Would it not be fair to say that, from the viewpoint of a young child, the extended family would offer greater support than a nuclear family? I have some evidence that this is so.
Further, bonds established within a clan, with (say) one’s cousins, are likely to be as durable as the bonds between siblings. My experience confirms this; one can be parted by an ocean, and yet remain bonded with other members of the clan.