I can assure you, lots of "classic EC architecture and even OOP architecture" games also have many Systems in the ECS vein, when they need them. Not for the per

I can assure you, lots of "classic EC architecture and even OOP architecture" games also have many Systems in the ECS vein, when they need them. Not for the performance (that's tied to memory layout in ECS) but when it's easier to implement a given piece of logic that way. Traffic, pedestrians, opponent AI, weather, mission flow, encounters, are a few typical examples.