I've worked with fortysomething guys that were "10x engineers" or "rockstars" when young a few times. One of them was very smart but really kind of a one trick

I've worked with fortysomething guys that were "10x engineers" or "rockstars" when young a few times. One of them was very smart but really kind of a one trick pony engineer, he kind of always wanted to use the same hammer to solve every problem and that got in his was of self improvement and awareness. The Dunning Krueger effect was strong with him. The other guy is kind of a legend and never ever stopped being a rockstar and kind of rockstared a few new fields and technologies again. He's also really humble but at the same easy knows exactly what he can do and what he can't do and is very good at always being at 100%.