Complexity isn’t simply the number of lines of code. Where individual shaders are adding linear complexity subtle interactions between different parts of a simulation can easily end reaching full factorial complexity.

As such AAA games favor independent systems which add as close to linear complexity as they can achieve. 3D models are a great example where extreme detail is largely irrelevant to every other part of the game.

That said, depending on what you’re measuring AAA games end up having wildly different levels of complexity.