Dealing with a know-it-all can be exhausting and there are times when your best response is to ignore their ‘helpful’ hints as much as possible.
They can often be close-minded as well–which means they can become a severe impediment to the creative process by blocking any idea other than their own. They simply know an idea either will or won’t work. Some know-it-alls can come across as opinionated, aggressive, brusque and even loud–all traits that won’t win over a lot of people at the office–and in fact can be easily construed as bullying behavior.
Upper management moved on to bigger and better things.