This is fascinating, thank you. As a counterpoint to your #2, what proportion people using $100-$200 headphones equalize them properly? This strikes me as sim

This is fascinating, thank you. As a counterpoint to your #2, what proportion people using $100-$200 headphones equalize them properly? This strikes me as similar to displays. Most people don't do any calibration, and reviewers tend to review both the monitor calibrated from factory and after their own custom calibration.