The only purpose of an exit poll is to provide a partisan media a tool to manipulate voters. Not only should they be banned, but I would favor the elimination of a state-by-state electoral projection until all polls were closed.
That's unrealistic. The polls in Hawaii and the Aleutians close very late, and have little impact on the outcome of the election.
Those who are tabulating the votes in states where the polls have closed cannot be expected to remain silent all night waiting for those western precincts to close.