Always read older stuff from Carmack remembering the context. He made a name for himself getting 3D games to run on slow hardware. The standard advice of write for clarity first, make sure algorithms have reasonable runtimes, and look at profiler data if it's slow is all you need 99% of the time.
And before that, 2D games (side-scrolling platformers were not a thing on PC hardware until Carmack did it, iirc). I think his main thing is balancing clarity - what happens when and in what order - with maintainability. Compare this with enterprise software, which is orders of magnitude more complex than video games in terms of business logic (the complexity in video games is in performance optimization), but whose…
For people who think game programming is less complex than enterprise software, I suggest the CharacterMovementComponent class in unreal engine which is the logic of movement of characters (people) in a networked game environment... With multiple thousand lines of code in just the header is not uncommon in unreal. And this is not complex because of optimization mostly. This is very complex and messy logic. Of course we can argue that networking and physics could be done in a simple naive way, which would be unacceptable in terms of latency and throughput, so all in all complexity is because of optimization after all. But it is not the 'fun' elegant kind of optimization, it is close to messy enterprise software in some sense in my opinion.