A few things - first of all, NFs have a hardon about "people change" because of NF's views about idealism and redemption, etc. Second, there is a good chance we differ on what constitutes "change".
For example, in high school my social skills weren't as refined as they are now. Over time, I've learned how to put people at ease while talking to them, started employing faux-feeler niceties in my day to day communication, and realized that some people are just the way the are because they were born that way and there is no sense in banging my head against the wall if they act irrational (knowledge of Myers Briggs helped a lot in this department).
But have I turned into an extravert? No. Became more of a Feeler? No. Has my general view of the world changed? No. Did the way I view and value people change? A little, maybe. I've grown to understand that there are more intricacies to human nature than I originally thought, and learned to value them for what they are. But did my attitude toward humanity in general change? No.
The changes that took place are more or less cosmetic. I would say I appear a lot more pleasant and socially graceful than I did in high school. Yet I am still the same "irreverent asshole" on the inside. I've just learned to adapt in order to make my life easier. Keep in mind, these cosmetic changes that took place are the first level of interaction, so if I had a stranger talk to my high school self, and then talk to my present self, chances are the stranger would say that those are two noticeably different people, while in reality, it's pretty much the same person, only the older me is wiser than the younger me. I now use discretion on who gets to see the "true me".
So as I've mentioned in a previous post, I've learned to adapt, as have you. I wouldn't consider any of that a fundamental change though. And yes, there are people who don't get wiser with age. I usually refer to those people as "retards".