High IQ is like a cheat code, that allows you to recognize what is really being evaluated in workers, and to focus on maximizing that. Things that usually matter are: how you present yourself, are you confident in your opinions and not caught being wrong by others, do you ooze enthusiasm, do you regularly seem to be doing a lot of valueable work (does not matter if you actually do it). Productivity is incredibly hard to measure in software development (outside of obvious cases, like a guy just not doing much), so it's not really measured.

High IQ, ideally with a bit of psychopathy, is really a killer combo.