> This information is visible to other employers that buy in to the scheme, and obviously favors the employer in salary negotiations with a candidate.

Meanwhile, it is an employee-rights win that the employer can't ask for your prior salary. Which of course they now already know.

We need strong laws that protect people from companies using data. Similar to credit-data usage for loans, companies should be limited to information on an application and in an interview when it comes to making employment decisions. They shouldn't be allowed to use social-media or past employment salary, or similar. At least not without explicit legal requirements and laws governing usage.