The overwhelming question I have when reading these responses is "don't you guys read salary survey data when you're looking for a new job, or at annual review time?"
See if you can figure out the difference between volunteering anonymized data with the exact level of granularity you choose vs. having all of that data and more involuntarily collected and sold in secret as a consequence of merely participating in the system we are all coerced into if we don't want to be homeless
But the salary data that’s available online to me as an employee is imperfect and extremely limited. This would be like if every employee of a major company sent their exact salary and demographic information to levels.fyi, which would never happen because it’s an insane sacrifice of privacy