And as a result, the person who took more Honors classes will be "more educated" (assuming the Honors / AP classes succeed in their stated goal). Therefore, the student that took the Honors classes is more competitive.
It comes back to the question of what universities should prioritize. Should they be optimizing for the fairest / most equal student body, or the most gifted / competitive student body?
More educated and more competitive are not the same thing.
What you want is the most talented, hardest working, brightest students. That's difficult to discern given the differences in the availability of opportunity. Scaling for availability is hard.
But it is clear that just selecting for the students who succeeded in the best environment will leave you missing out on potential. And worse, that rapidly becomes self-reinforcing, since the next generation of students will be influenced by your choices on this one.
Even when parents are paying for the lesson, it's still the student that has to do the hard work. But a student with less help deserves more merit for achieving the same.
Gaming implies that your metrics are being ruined by moving towards an opposite effect, not that they fail to be perfect. Similarly, doing well in the IMO could be a predictor of wealth and circumstance, but it's also a signal for math talent.
If we're saying that AP tests and classes are too easy, then of course people can have a discussion about increasing difficulty.
All I know is there are trivial AP classes like AP Government, AP Econ, AP Art, AP Computer Science, etc. at my school. Almost everyone got an A and a 4 or 5 on the test.
In 2021, Under 50% of students got a 4/5 on compsci, econ (both of them), gov, and Art. The only thing which can charitably be included is AP drawing, which about 52% got a 4 or above. The high scores in your classes have more to do with school quality than anything else.
It comes back to the question of what universities should prioritize. Should they be optimizing for the fairest / most equal student body, or the most gifted / competitive student body?