I find the 'deferment of gratification' an interesting one, for me personally..
The deferment perspective is one of the attributes associated with higher IQ's. (Knowing my IQ, I can put myself in the 'right area of the spectrum').
My personal deferment of gratification is was very low. I really did 'live for the now'. For decades.
No so much anymore, but still my 'default setting'

In trying to square the circle , the only thing I can settle on, is that because of my upbringing, I'm very self sufficient, and don't have much fear of not being 'able to cut', whatever the immediate circumstances.
Ergo the 'fear of the future' - an essential component in the 'deferment of gratification' - is absent.
(and not having much of a parental drive -or any kids- may also play a big part . I dunno..)

What we need in schools is real education - philosophy. And more philosophy. So many of all the other problems will fix themselves if kids were educated with critical thinking and logic as the basics - like the first 10 years of education!