How to file an appeal of a National Merit Finalist rejection?

This whole thread just points out the weirdness of the whole National Merit concept. Why is there such a big process and high stakes around a practice SAT? Why not make it about the real SAT instead? Why would schools covet anyone who does well on a practice test when the real test results and all kinds of other attributes are readily available? Even though my son may benefit from this “honor”, it doesn’t seem like it will persist much into the future.