One might argue that the only reasonable advantage we have that previous cycles did not is that of the Avatars. Remembering they're all linked back to the Calamity, and is arguably how it perceives us.

[Sephiroth doesn't linger too far in the back of many of these discussions, hoping for a thread to come around that he might be able to learn something out of. The Avatars are not discussed enough, in his opinion.]

To take on the Calamity itself, seems to me like it might be like a grain of sand trying to stem an ocean.