So if your managers are totally failing the employees they are managing... you cannot seriously correct them?
But presumably you expect the employees to take serious correction. So this really reduces to an unspoken code that management shouldn't be treated this way.
You can correct somebody respectfully. I think Ben could have had exactly the same outcome without coming across as a jerk.
I'm not judging Ben either way here; sometimes a situation requires being a jerk. But the more managing I do, the more I believe that if a manager has to be a jerk it's because they've messed something up elsewhere.
But presumably you expect the employees to take serious correction. So this really reduces to an unspoken code that management shouldn't be treated this way.