As far as my personal opinion goes on, "level of apocalyptic" it needs to be able to still have some sense of "fun" even with dire situations overhanging. Get TOO dire in the setting, and I think that drives away some of the entertaining things about the characters and world setting in the first place. There still needs to be room for the lighter side of things, even in light of a serious atmosphere.

Of course, still consequence and new looming threats, but! The SOL options shouldn't be lost, and I think there are ways to do it without making it grimdark as all get out. (Plus, that leans towards some degree of making it accessible and appealing to new potential players, as well.)

If anything, I think even using the word "apocalyptic" for even for how it's been described is very much a misnomer, and that alone can be a turn off for some (as this thread has already displayed once.)

That's my two cents, though. :)