A major theme of f. Scott fitzgerald's work was the idea that the post-war world

was empty and meaningless.

Explanation:

Francis Scott Fitzgerald belonged to a group of important American writers of the 1920s called the "lost generation," since he had trouble adjusting to life in the postwar era and was considered a pessimistic novelist. In that respect, he did not think that the post-war lifestyle of the 1920s was fascinating or advantageous. In fact, he expressed a sense of desolation and frivolousness in his works.