@Armorpiercer hmmm in majority of anime manga I saw the strength of dragons is far below demon lords, so even if she did solo the dragon it doesn't mean much for the whole hero vs demon lords. If they did killed the demon lord I think their reception won't be so small limited to their own village, most likely the whole country and big cities will grandly received them and mourn while celebrate the end of demon lord, but it seems they're just another hero party who failed to kill the demon lord and slowly forgotten.
There's some scene of the normal village when the hero is still just small kids and a relatively normal cities when they found the mage, so it's not like the world is in peril and fighting all 24 hours everyday, most likely the only hot area is the frontline and the rest is quite normal just like the last scene. The long trails of blood also suggest that she drag the hero body into safety, that is not needed if they did defeat the demon lord. The ending is also like a hint of another hero party that lost their member but need to kept going to defeat the demon lord, so they left the corpse to the mage for journey back home.
In any case, she said they're defeated, not draw or even killed the demon lord so I can't imagine they find success in their journey. But this manga is not seeking for happy or meaningful ending for the hero's party, the hero is defeated and dead, the tragedy is simply told like that.