That is the opposite of my experience. The apocalyptic settings and breaking settings are favored by GMs who like beat down and torment players (rather than the characters) and call it fun to destroy what they've done and spit in their face and deride them as weak if they don't eat all the crap like it was candy.
That's just because of bad GMing, instead of something inherently deficient in the setting.
Take Exalted (which I am running right now):
First Age: A golden utopia where almost everyone gets all the basic necessities of life - even if some of the 300 demigods ruling over the world are slowly sliding over the deep end. In my opinion, it's hard to GM for this setting since there are fewer external threats which could be fought and the PCs risk getting overshadowed by some of those ancient demigods.
Second Age (the default setting): This definitely counts as "post-apocalyptic". The Solar demigods of old have been overthrown, their usurpers generally made a mess of things, a great plague wiped out more than 90% of all people, and an invasion of entities of primordial chaos from the borders of the world threatened to swallowed it. A powerful woman who became empress beat them back and ruled for more than 700 years, but she recently vanished mysteriously, the Realm that rules much of the world is on the brink of civil war, barbarian hordes lead by creatures half man, half animal are sweeping in and threatening to destroy civilization, and the forces of the Underworld - the realm of the Dead - are rising up and attempt to kill all life. And in the middle of it all, the Solars of old are reincarnating - some of whom are just as arrogant and prideful as their predecessors, and they carry a
grudge.
The Second Age is
easy to GM. You have all sorts of threats to throw at the PCs - and the PCs can really make a difference, especially if they play the (default) Solar Exalted. These are really very likely to rule a rapidly expanding kingdom in short order (if they aren't killed yet).
And that's what a post-apocalyptic setting can be - an opportunity for the player characters to rise to the top of the food chain very quickly.