“Four and a half Vulcans” could have been much more subdued and less divisive if Spock had had the confidence to put his foot down and say, “No you are not Vulcans. You are merely humans who have been temporarily enhanced with Vulcan DNA and epigenetics. Without the proper training in Surak meditation, you will all go insane in a matter of days.”
And since we are told that the Vulcan serum was, “derived from Spock’s perceived experiences,” I wonder how much of the funny Vulcan racism reflects Spock’s own struggles and self-doubt about his own Vulcan bona fides.