There is actually an alternate ending, that does not display that scene.
The scene that you described is not in the original script. Is not uncommon that the studio makes requests for changes (on behalf of a more comercial approach for the movie).
With or without the scene, you could still raise the question about
if 2024 is a simulation or not. And the world in the upper level, is a simulation too, like an endless Russian doll? How would I make sure I reached "the top", "the real thing?".
As with other SiFi works that deal with the perception of reality, like Ubik or The Three Stigmata of Palmer Eldritch the appropriate question of a character in that world would be "how do I tell what is real and what is not?", "How could I be sure?".
That ending is just an artifact to bring some of that reflection. Even,
that abrupt disconnecting could tease the spectator: "how could you be sure your world is not a simulation too?"