If you've ever worked for a YC or Sequoia company, you're in a secret database with who you worked and how much you made that is accessible to other founders. The additional context is critical for startups to make competitive offers to startup employees. I don't see what the big deal is. If a worker is working at a company A making $80k, and they try to get a job a company B making $90k, the owner of company B needs to know they were only making $80k at their last firm, so they can make a good offer of $85k. $10k would be too much.