What Is Lost

'In “On the Road,” nothing stands in the way of the authentic, except the rules of formal life; when they have been overcome, the glittering night opens to anyone who desires to enter it. The naïveté of this is astounding, but so is the power.'
Karl Ove Knausgaard, My Saga, Part 1 

Which is also a pretty good description of that form of science fiction sometime called 'core'. But must be overcome, to write in that form? What is given up? What is lost?