I feel like some people would make it their goal to kill wall of flesh for the sole purpose of throwing the world into chaos by adding massive amounts of world evil and new dangerous creatures.
i gotta wonder how people would do these things, exactly... from what i understand of the scenario, no one would be able to do anything.
for example, some of the people here thinking they could take down monsters and get "endgame gear" are kids.
even the adults, how tough do they think they are?
the mistake is viewing it as a game... the scenario here is terraria seeping into REAL LIFE... you don't get infinite lives, we'd still be playing by the rules of reality, just with terraria's monstrosities roaming about.
think you're gonna carve a wooden sword and beat grizzly bears into submission as the world currently is? if not, i highly doubt such a thing would work against gigantic monster worms and eldritch abominations.
i've seen people do woodworking, and it's generally... not good quality... so how does everyone here expect to not only craft swords and other weapons, but do so using alien materials?
again, it's not like governments would just crumble... they'd probably mobilize the military and secure these areas as soon as possible.
then again, i guess i'm just taking the whole thing too seriously.