The most surprising thing to me is how I feel about math and academic subjects. First decade in the workforce I thought math and academic CS were kind of a was

The most surprising thing to me is how I feel about math and academic subjects. First decade in the workforce I thought math and academic CS were kind of a waste of time - it was so easy to be productive and respected as a programmer without it, just by using logic and thinking. But... as you get more senior and start dealing with concurrency and distributed systems, surprise! Mathy stuff is valuable. Big-O stuff, but also just recognizing what different scales feel like. It's weird to realize that things like e and ln are all of a sudden directly relevant to life. It's disappointing that a lot of math classes in college never seemed to focus on the intuitions of what those concepts feel like. Anyway, I would have spent more time earlier on getting facile with mathematical thinking - critical thinking, bayesian reasoning, advanced math, etc.