Here's my hypothesis: in healthy individuals, video games do not lead to violence. But in an unhealthy person who is already looking for an outlet, shooter game

Here's my hypothesis: in healthy individuals, video games do not lead to violence. But in an unhealthy person who is already looking for an outlet, shooter games provide a template to follow, that may allow unfocused anger to turn into an actual plan. Is there any good science on this idea? Guns and mental health problems had already been present in America for decades before mass shootings started happening. Video games are the only new ingredient I can see. I can't take seriously any full dismissal of their role until that timing is explained.