At my workplace, we have about 60 scientists and engineers. The author's observation is accurate, that most people never use math beyond Excel and 8th grade math. They also never use most of the theory that they learned in their science (including CS) and engineering educations. The typical career arc is to get through college, then sit down at a CAD workstation, or programming terminal, and forget all of your math a…
I think people don't even realise when all that extensive math they studied is even helping them. They may have forgotten or not used the specifics in real life, but if they originally understood it well then they probably gained an important subconscious intuition that shapes, optimises and/or narrows that design trial and error. And the best engineers have a great subconscious intuition for finding solutions.
Note: I studied Civil Engineering, so my math background was nearly all Trig and Calculus rather than the Discreet Math, Logic or Number Theory etc that a Computer Science degree might entail. I've forgotten nearly all of it and never really used it IRL, but I can still appreciate having a 'feel' for relationships between changing quantities etc that others without that math background don't seem to have. And having spent far longer working with software (self taught) than I ever spent with Civil Engineering, I often wonder what subconscious intuition of CS style math I'm missing that would help me.