Don't forget the other options, such as but not limited to...
Bad ending: Everyone is perfectly happy as slaves of the evil overlord. War, diseases, poverty no longer exist, but neither does free will.
Good ending: The villain has been defeated but this does not magically fix the damage they caused and there will be a lot of rebuilding and healing to be done.
In gaming, the 'true ending' is often the one that requires a little extra work, the one that keeps the story going with the player having to move towards the goal of a 'happy ending', the one most players seek to get.