I don't believe salaries are public but instead salary ranges alongside job postings. Someone please correct me if I am wrong as the former would be a much more

I don't believe salaries are public but instead salary ranges alongside job postings. Someone please correct me if I am wrong as the former would be a much more valuable tool for labor. Under the latter the range for SWE could be 40-80K and so a new employer could possibly find that job posting from around the time you say you were hired but still shouldn't have any idea if you were making the 40k or closer to the 80k. I believe this is intended to curb the market behavior of offering someone a pay you think they will accept rather than offering to pay based on the value of a role. Turning the difference between those two numbers into cream for upper management to butter their bread is the status quo in America at the very least and likely in all of the western world, but leads to systemic discrimination amongst protected groups with weaker negotiating power.