Yeah, unmarked spoilers ahead...
I've been wondering this for a few years now...
Lets ignore the Compilation of Final Fantasy VII for a moment and think back to the late 90s/early 2000s, when Final Fantasy VII was still it's own self contained storyline and the sequels hadn't been thought of yet...
At the very end of the game, after we see a giant explosion flash and the fate of our heroes unclear, we see the credits roll and then we see Nanaki and his two babies running through a canyon and howling over a scene of the remains of Midgar 500 years later, completely taken back by nature. We see birds fly over, the end. Absolutely no signs of humanity are to be seen after the credits roll, aside of some childish laughter over a black screen at the very end.
Okay, fine, Midgar has been destroyed, but we get a pretty panoramic view of the extensive landscape in the distance. Isn't it odd that all those people evacuated from the biggest city on the planet wouldn't have established a new city somewhere near by in that 500 years? No, all we see is lush greenery untouched by man. Not even any roads or anything, not a single sign of human beings present, only the ruins of Midgar signifying but a memory of humans.
So did humanity survive meteor's impact? Did they all die from that blast? Did they just die off over that 500 years, unable to recover from the post-meteor apocalypse? Or perhaps they died off from something else?
What message do you think the original development team had in mind?