Linux tends to be faster because the kernel is just far better optimized than Apple’s appears to be. Massive sums of money (and person hours) have been spent speeding up Linux networking, file systems, scheduling, etc. and it was all sent back to mainline.
Apple’s kernel team can’t possibly compete based on resources alone. They do their best but MS, Google, Amazon, Redhat, and so many others are constantly improving Linux to squeeze out every last drop of performance.
So in many ways Linux is better optimized. I remember one of the developers posting a few weeks ago about just how much faster code compilation was under Linux, because the file system layer is so much better. It was like 6x or something. Sort of an accidental ideal benchmark for stressing that.
But you won’t be disappointed.