Interesting point is 40+ years ago cpu/memory was very expensive and software engineering and coding labour cheap, relatively speaking. In this scenario the code often could look however it needed to fit into available resources. "Clever" coders wrote terse and often wrote obtuse code that fit into whatever hardware resources were available. Maintenance or modification at times was one step forwards and two steps back with all sorts of side effects revealing themselves.
These days, the software engineering and maintainers are very expensive relative to the cost of the hardware, so the code should use all the memory and resources it needs to be as readable and maintainable as possible.