Okay, So Let's Recap—Conformitygate, Dream Worlds, Lost Signals, and No Exit
Robin and Vickie call it a dream world instead of another dimension. As if this whole ordeal took place inside someone's mind.
Vickie has an exit sign above her head after Robin "wakes her up" to the truth and the demos do not attack them (but ate the soldiers).
Robin uses the intercom to signal danger is coming.
In the shot is a Garfield quote, "It's not the valleys in life I dread so much as the dips," where dips is short for dipshits as in Derek, bullies, or mouth breathers. Dreading, or procrastinating on, dealing with them.
Who is always late, pushing the inevitable? 🤔
Lucas has a bright exit sign above his head. He says everything sounds like "déjà vu," an illusion of memory, to Mike. The reception sign is between them where the intercom is. Their exchange is similar to Vickie and Robin's.
Yet, the bulb in Mike's exit sign is not bright or lit up like Lucas's and Vickie's. He's drinking coffee trying to wake up.
Right after, Mike has a strange sense of déjà vu.
Mike's expression in the hospital is the same in the epilogue, when he hears a signal, and notices discrepancies.
So while in the hospital having the strange feeling that his new situation has happened before, a glitch in his brain that mistakenly signals familiarity, he sees A Wrinkle In Time, an anti-conformist story, and another book on fairy folklore ("fairyland," what the Upside Down was once called by a homophobic bigot).
It's an exit sign signaling the plot or reality he is currently in is an illusion.
This meta storytelling using "signs" is very similar to Labyrinth, a plot that took place in a dream world. We see everything in the main character's room that was used for the story she made in her head.
A labyrinth, in the heart of the Upside Down, is what Steve called "made-up bullshit."
This self-reflexive meta is used explicitly in Mike's dorm room during the epilogue with items around mirroring the plot after he is called a storyteller. Only he has a one-way sign above his head, not an exit.
Earlier, Mike's red-light signal, aka the WSQK tower, was broken.
From the radio station, Robin, for one last time, signals a warning that the party is graduating, changing, moving on. Most of them near red exit signs, as they chose the door to escape this illusion.
Meanwhile, the on-air sign is cut off from view. Instead, the exit sign we see from the booth is white, which is distinct from all the other red signs.
The white "wall" sticker is reminiscent of the Pink Floyd tapestry in Mike's dorm and their album on conformity. A sticker of The Smiths, recalls their most famous song about feeling left behind and losing hope on finding love—another kind of mental wall.
Where red means escape, white means acceptance of the reality you are in without challenging convention.
Mike does not have an exit sign after the signal is broken (going from a two-way to a one-way). He leaves through a white door that we know from a previous scene leads back into Camazotz.
He chooses not to change and decides to conform, procrastinate, trapping himself in Vecna's dream world. Why? Every red exit sign leads to finding love, truth, and self-acceptance—something he's always been scared of as his love defies convention and bigotry.