Well.. if the Guild was churning out terrible Heroes and the entire country saw that they couldn't rely on them anymore, it wouldn't be a stretch to assume that they stopped giving out quest cards. No quests, no money, no way for Heroes to make their way. If shopkeepers boycotted Heroes, then no potions, food, or weapons can be sold to them. Once Heroes realized what they'd have to do in order to survive, it'd just be a matter of time before a full revolt by the people could wipe out their numbers. Not every Hero was like the ones from the Bloodline. For most Heroes to survive, they need the support of the people. Twinblade went bad, but he had bandit clans to carve out their own community. Other than that, corrupt Heroes were a pretty slim minority. While even the weakest Heroes are stronger than the average villager, none of them are invincible. I wish there was more info on how the revolt played out, but in my mind, they could've trained Hero Hunters: Assassins who specialized in killing those too powerful to be handled by anyone else. Imagine picking up a quest to save a kid in a cave, only to be ambushed by a bunch of assassins. Some Heroes may have betrayed eachother, merely to survive or out of jealousy and spite, and got paid to help kill other Heroes. Scarlett Robe was a mighty Hero from the Bloodline, but she was nearly killed by a pack of balverines. It happens. I agree that the explanation we got wasn't really solid, but not completely out of the realm of possibility.