So... What comes after Apokalips War? (DCAMU) (Spoilers)

[Giggling Ghast]

The galaxy would certainly fall into chaos without the Green Lanterns to police it. And other cosmic villains would almost certainly move into the gap left by Darkseid - Mongol, Brainiac, Imperiex, Starro, Despero, Sinestro, etc.

Besides, the important thing here is that this version of Damian Wayne has been erased. Any alien race that watched Son of Batman would agree this was worth re-starting the timeline.