I never claimed it did. Compilation is an embarrassingly parallel task. This means you can increase the number of threads by a much much larger amount before you hit Amdahl's law. That is not true for video games unless you count what runs on GPUs. Not only can it be less obvious on what to parallelize in a game engine. You quickly start to see the parallel slowdown/diminishing returns in game engines. Further, not every thread in video game is going to use the CPU at 100%, a lot them will be waiting on IO, and not using any time slices till that IO task is finished.

Games do not scale like compilation, it does not matter what engine or how new that engine is.

https://en.wikipedia.org/wiki/Embarrassingly_parallel https://en.wikipedia.org/wiki/Parallel_slowdown