Horatian satire is gentle, playful, and aims to correct folly through amusement and light ridicule. Juvenalian satire, on the other hand, is biting, harsh, and uses scorn and indignation to attack vice and folly. It aims to provoke anger and outrage to inspire change.
"Harrison Bergeron" uses dark humor and a bleak, dystopian setting to fiercely criticize unchecked egalitarianism and the dangers of suppressing individuality and excellence. The story's tone is far from playful; it's grim and unsettling, aiming to shock the reader into confronting the potential consequences of its satirical target. Therefore, its approach aligns much more closely with Juvenalian satire.