It certainly sounds like you "understand that experience is often the best teacher"! As far as not caring what others think of you - I believe it comes with ag

It certainly sounds like you "understand that experience is often the best teacher"! As far as not caring what others think of you - I believe it comes with age. As social animals I believe we evolved to care a lot about the feedback from others while growing up since that helped us get along and survive in our tribe/clan. As we get older, we're the ones providing that feedback. Plus, survivorship bias makes us think our way must be right. That's why old people get cantankerous.