OP is also correct in that the following is how HR at almost every large company thinks about comp:
1. Comp is usually not set by a Hiring Manager and is specifically based on "comparable" which is based on job type and location.
2. Job type and location is by far the easiest way to create a heuristic for pay rates because the data is public
It's basically impossible to individually value everyone's contribution consistently and without bias across hundreds or thousands of employees - plus I don't think people would want to actually be judged with any method that puts granular measurement on something as vague as "value"
So if you can come up with a better way to determine pay *at scale* other than the open market approach, I'm super interested.
The only way to do this in my mind is to never pass -- lets say -- 100 employees.