Yeah. I'm flirting with sixty, and even now almost didn't remember that little bit of level-headed wisdom in a recent business and work situation. I'd forgotten it and was about to make a probably stupid move until I stopped and remembered. They're probably not thinking about me a whole lot, so it's dumb to approach it as if they were. The peace of mind was sudden and sure.
I was over forty, too, when I stumbled upon my personal "set me free" bit of wisdom that widened my whole perspective, and that was "You can accomplish anything if you don't care who gets the credit." That one ... hit me like a platinum sledgehammer! It set me free!
I had a similar one when I was about 36 that gave me a pretty good push forward. Something like "You can accomplish anything if you don't care whether you succeed or not." Some years later a friend defined the underlying problem I was working on there. "Hesitation, doubt and fear." And the cure. "Don't have 'em." lol
That wasn't as liberating as realizing that all the people who were judging me were being manufactured in my own brain box but it did give my confidence a big boost.