I would have genuinely laughed out loud if someone said that to my face. My reaction would have been to give him a reality check - "My man, you may know some things, but definitely don't know it all!". Perhaps, also ask him - "Have you considered that some of those people considered talking to you as dealing with a toddler who thinks he knows it all?"
Then he laughs, turns away and talks to somebody else and leaves. He will still feel superior and not waste time.
See for instance https://youtu.be/ye8zcgxWMDc where he only stays as it's a major presse event (the guy buy his side was running for chancellor to succeed Merkel; and yeah the questions were "dumb" but with your questions you won't get a better response)
