Elegant, tight, and efficient code mattered back in the days when a machine with a 20 MHz processor and 8 MB of RAM was considered a high-end workstation. You really had to understand what your hardware, your OS, and your compiler was doing in order to produce decent software.
Nowadays, such esoterica is relegated to the tiny niches of systems and embedded development.
My side project right now is flight control/readout software written in assembler for the C64 which will control a virtual spacecraft inside of my lua programmable 3d/physics libretro emulator front end.
I am really enjoying working inside of Turbo Macro Pro. It is an interesting challenge to make the assembly code efficient and easy to understand.
Nowadays, such esoterica is relegated to the tiny niches of systems and embedded development.