Quote Originally Posted by EaraGrace View Post
This is the riddle that ultimately underlies why the Sundered were able to survive. You are right, being mortal doesn’t solve the problem of destroying your species, the risk is always there. But being immortal doesn’t just make it a possibility you will be a Dead End, it necessitates it. The notes left in the aplenty, the statements of the Ea in Ultima Thule, all suggest the only way for an immortal species to overcome the consequences of their immortality is to not be immortal anymore, to choose to relinquish that and instead accept mortality and weakness. It’s why the Plenty citizens wax fondly for the time when they were struggling. They understood that risk of failure success rings hollow. So yes humanity is still at risk, but they can still avert that end.
My bad for replying to stuff in two different posts, but I don't think this follows. Not being immortal doesn't somehow make you immune to inevitably coming to an end, if just means it'll happen well before the fate that terrified the Ea came about. Escaping the consequences of immortality isn't escaping the consequences of being alive at all.

Mortal civilisation will die just as certainly as (some of) the Ea or the plenty did, there's just a much wider variety of things that could do it. Even if you were super lenient and did allow a society to continue existing for as long as the Ea, how are they supposed to get around the heat death of the universe? The plenty had issues others could dodge, the Ea did not.