Our introverted intuition does grow with age, in some cases substantially.
But, it must be noted that even significant growth still leaves it as a "background process."
We make abstract connections, often in real time while problem solving, we are on a journey to self actualization, and we do care about our communities and the greater good of mankind. We just don't get into it so much that we lose touch with our favorite of all: Se!
I've become more grounded in the past 15 years. I've only been aware of MBTI for 2 years, but relatives that have known me my whole life say that I walk, talk, laugh, eat, etc. just as I did when younger, same attitude, same mannerisms. That being said though I'm now 35, and I can assure you that I am way more easy going, calm, level headed, and self actualized than at 20, but at both ends of this spectrum I have been full on ESTP.
Maybe Ni has something to do with this more than I am consciously aware of. But I do know that I am more content and happy for the right reasons now than ever before. And whatever helped me get here is cool with me.
P.S. I'll still be a wild, hyper bastard at 60, don't get your hopes up.
