Earlier quoted context omitted.
What political objective is accomplished by not coddling children?
That's the point; children would die otherwise, by the very biological nature of our species. What the various kinds of "avoid coddling" types want is determining the details of what should be allowed to traumatize them, specifically, in order to shape society.
As far as I understand all Haidt calls for is to remove the boundaries that have been established over the past couple of decades, or what selectivity are you hinting at here that are part of that supposed plan to shape society?