News flash: not everything you see on TV is real—not even reality TV. Or news. And the same goes double for the world of "Harrison Bergeron."
About half the action in the story takes place on TV. The television puts some emotional distance between George and Hazel and what's happening on TV, i.e., their son getting shot to death. But how do we know what happens to Harrison on TV is real? After all, he is flying through the air like Peter Pan on steroids.
Or, consider this: even if it is real, is it live or a taped recording? Maybe George wanders off to get a beer because he's seen this one before—and no one likes reruns.
The symbol of television helps us come up with a slightly less political angle to the story: maybe it's just saying that TV turns us into mindless zombies who will do or believe anything. This makes TV the perfect medium for a government to control its people (or for Vonnegut to satirize the fear that TV controls people).
Here's a clue to just how big a deal the idiot box was in the '60s: in 1961, the same year "Harrison Bergeron" was published, chairman of the FCC, Newton Minow, gave a speech about television, calling it a "vast wasteland."