The Ph.D's that I know have a specialty, but also have knowledge in most areas. You would never want to play a trivia game against them.
They just store and access knowledge very well - almost a database.
Just saying, I have a PhD and nobody should fear playing a trivia game against me. I take inspiration from that bit in Sherlock Holmes where he castigates Watson for giving him the irrelevant piece of knowledge that the earth goes round the sun, and explains that he's now going to do his best to forget it.
