By the same logic, people working in transportation around the time Ford Model T was introduced did NOT diminish 100 years later. We went from about 3.2 million in 1910 (~8% of the workforce) to 6–16 million in 2023 (~4–10%, depending on definition). That is the effect of a century of transportation development.

Sometimes demand scales, maybe food is less elastic. Programming has been automating itself with each new language and library for 70 years and here we are, so many software devs. Demand scaled up as a result of automation.