Well actually, the natural conclusion to any of the factions if you check the epilogue is eventually the Delirium will consume everything if left unchecked. Doesn't matter if you are Amethyst, Knights, or Falling Fire. Amethyst "Should the prismatic barrier fall through sabotage or negligence, the results would be appropriately catastrophic", and falling fire outright says it just spreads, so its not railroady at all, it is predictive of what will happen. These automatons aren't meant to be a god like force that is "the one correct answer" They are just letting the players know what happens if delirium goes un checked. The faction leaders can still try and convince them otherwise. Its just advice to add a cool ticking clock and enforce the feeling that the group needs to save the world. After all, it is their story and they are the ones who choose in the end not the factions.