Right, well a lot has changed since your old co-worker grew up! When I was a kid there was no internet. We did sit around a fire and drink beer a lot when I was a teen. When I lived in the city, we all congregated in some remote area and drank (until the cops showed up). Or someone's parents went out of town and we partied at their house (until the cops showed up). The difference was in the city there were arcades, and we could go there and drink and do drugs in the parking lot. In the country towns, you might have to drive a bit to find something like that. Teens just find a way to party, no matter where they live. Doesn't really have anything to do with echo chambers.
About the crazy ideas, though. You probably don't mean to, but you are making it seem like it's only the country yokels buying into conspiracies. Like someone crammed into a city is somehow immune. The internet should have made the echo chambers disappear, but media and politics combine to make sure we stay mad at each other, because outrage sells, outrage gets votes, outrage keeps us busy fighting each other and we pay less attention to what they are up to.