The way it was written, it would have needed to have some extremely creative writing to make the ending work in a way where there could be more seasons. People in this thread have offered solutions such as all of the characters making their own zones and a new character experiencing them, them being clones in cryo of their actual versions, etc.
Creative solutions were not chosen, the safest, lamest one was. Because of that, it's VERY hard to sequel 'welp guess we're all trapped forever! YIPPEE!'.
They could do something with recovering the people who abstracted since they know there are no rules and nothing matters anymore, but that would be a surprising amount of insight compared to what we've gotten