haha absolutely it was real. And I died from it.
The issue they discovered is that the real danger comes from bottlenecking, where a lot of people are forced to be in a tight enough radius to spread it (AKA banks and auction halls). The problem with the study, I've been reading, is that in this game the only way to do your shopping or banking or anything else is to go there, and IRL you don't have to interact. So it helps give a rough model but it's forcing a lot of conditions that don't work in real life.
Still really interesting stuff. My wife's Epidemiology professor talked about it.