There's a large cohort of people who don't list their real reasons for leaving for the sake of departing on good terms and to avoid burning bridges unnecessarily.

Exit surveys don't fix a rotten culture and incompetent managers. We can only hope the higher ups look at the numbers and start asking why certain managements have a higher turnover rate then others.

A few anonymous surveys targeted at those teams from people who can't as easily uproot their lives to leave the company will tell you what's going on.