I’m not a parent, but going by pop culture, it seems like literally every child has the same fears.
In pre-modern times, I imagine that they’d be sleeping in the same room as the parents, but if modern notions of privacy don’t permit that, seems we could at least design an enclosed capsule or something.
The people who think not having it be one means children are avoiding rather than overcoming their fears
It may not have been intended as such originally, but if you defend the design on that basis, it becomes intentional.