Are you sure you’re not confusing this with the concept of “binning”, which is a pretty standard practice for chips?

You manufacture to a single spec, expecting there to be defects, then you identify the defective units, group them by their maximum usability and sell the “defective” units as lower end chips. IE, everything with 24-31 functional cores gets the “extra” cores disabled and shipped as a 24 core, everything with 16-23 functional cores gets shipped as a 16 core, etc