No reason why my coworkers should make more or less than me if we have the same title. Making salary information public either through averages per title or ranges (upper and lower) should naturally even out the salaries per title. As things stand, some people are privileged in all sorts of ways when it comes to a company’s undisclosed salary ranges. For example, in my last role I had a friend in the company who could confirm two separate salaries for the role I was applying and I was offered 10% lower than those two salaries. I can ask for a 15% increase in my counteroffer and be confident this is a valid number. If I didn’t have friends who were in the industry that weren’t comfortable sharing salary ranges, I’d have to stick to the Levels FYI site, but my last company wasn’t on there.
When I left, I learned new hires, who were new to tech, earned less than I did when I was at their title. It may be awkward socially to have people know how much I make (or even within a range) but it’s better than the economic disadvantages that unconnected applicants face in today’s job markets. Hope that offers some insight.