I'm guessing the cutoff point is about age 50: much older than 50 and you were in school before electronic calculators were a thing (mid 70s), so engineering would require a slide rule.
Bort is younger than that but is colossal enough of a nerd that he can do slide rules. Never learned chisanbop, though.
We had a box of slide rules in the supply cabinet at my middle school. Nobody had used them for years, so they let me take a couple home. I keep one in my desk drawer just in case.