I'm just reporting on an interesting study, and am not myself proposing anything radical. Your summary sentence is accurate for the gist of the research. The authors also teased out of their data that it is not overtly pathological behavior on the part of your peers (hospitalizations, arrests) that contributes to your own future problems. From this study the conclusion is that it is not clear how their genes influence you, but the most likely assumption - addressed by the authors and reviewers - is that it is more innocuous-appearing behaviors of your peers that can push your own behavioral patterns in directions which lead to bad outcomes.