I mean, obviously parenting matters, right? You can't just drop kids in the wilderness.
What's actually being said here is that if we remove the extreme cases, the people who aren't really fulfilling the role of "parents" as they should, the normal diversity we see among various types of parenting isn't really a big deal as far as outcomes are concerned. (This is still a bold claim, because, as you said, we might just not be aware of the slice of diversity that matters.)
What do you mean by "extreme cases"? One culture's "extreme case" is anther's typical parent.
If it's worth saying, but not worth its own post (even in Discussion), then it goes here.
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