I work in an industry where salaries are transparent. In my experience, when everyone in the industry adopts salary transparency, it just tends to cause salaries to converge to market rates. Whether this is a good thing or not depends on your point of view. I tend to think this is a good thing for employees, because it causes companies to respond more quickly to market signals that cause increases in salaries. On the other hand, this allows the most profitable companies to essentially set the market rate, which can be uncomfortable for less profitable ones.