Various programming paradigms (modular programming, object-oriented, functional, test-driven etc) have developed to reduce precisely this cognitive load. The idea being that it is easier to reason and solve problems that are broken down into smaller pieces.

But its an incomplete revolution. If you look at the UML diagram of a fully developed application its a mess of interlocked pieces.

Things get particularly hard to reason about when you add concurrency.

One could hypothesize that programming languages that "help thinking" are more productive / popular but not sure how one would test it.