Alright, my Amazing Digital Circus hot-off-the-presses theory is that there is no escape. They're stuck in there forever because there's no where else for them to go.

We see the computer that houses the circus, and the headset that Pomni describes having worn before showing up there. Conspicuously missing is the actual body of Pomni. Or anyone else, for that matter. The implication SEEMS to be that this machine houses the entire circus, rather than this being an online experience hosted on a server. What I'm saying is this seems like less of a Sword Art Online experience and more of a Soma one. I think that headset takes a brain scan of whoever wears it and downloads a digital version of their consciousness.

It makes the reveal of the sheer number of people who have "abstracted" and completely lost themselves make more sense to me. You'd think the authorities would hear about it if a ton of people went missing, or went insane, or went completely brain-dead while wearing these headsets. But if the people out in the real world are completely fine and continue living their normal lives, then who cares about the endless suffering of their digital counterparts?

It also makes the entire concept of a consciousness abstracting make more sense to me if characters are coded onto the machine rather than hosted by an actual living brain. A character who "goes insane" and has corruptions and aberrations in their code could start glitching like that.

So yeah that's my hot take. An exit can't take them anywhere because there's nowhere else to go. There is only circus.