> https://github.com/rui314/mold would suggest otherwise.

Does it, though?

I mean, if you read that link you'll notice it boasts the linker's performance by comparing it with cp and how it's "so fast that it is only 2x slower than cp on the same machine."

Is cp supposed to be CPU-bound?

Yes, but that's for mold, which is multithreaded. The original context of this thread being the question of whether a linker would see speedups from multithreading. Most people are using traditional single-threaded linkers which are an order of magnitude slower than mold. The fact that mold is so much faster suggests that a linker does indeed see big speedups from multithreading.

The data the linker is running on will generally largely be in memory (in their posted example, which is a warm compile, completely in memory).