Well said. I've had similar thoughts on that in-between state, inspired by Ernest Becker's Denial of Death, for instance.

I also wonder whether this analysis can be extended to the collectives that occupy different stages of historical accumulation of knowledge. Was there a prehistoric childhood of our species (in terms of the blissful ignorance that comes with the lack of much accumulation of knowledge from previous generations, owing to the lack of writing and art)? Is there a state of collective jaded maturity? Or is there a cultural cycle in this regard, as Spengler argued?

Anyway, it's interesting how teen existential angst is usually shut down when the teen takes on adult responsibilities. We mostly "outgrow" that confrontation with our existential condition, which means not that we've solved the problem but that we've become distracted with the mundane problems of our job and our family life.