- I'm not making the claim that video games lead to violence, I'm just saying that we should apply the same level of analysis to studies supporting views we already have that we do to supporting views we do not already have. If this study was well done, great! If it was poorly done, then it is appropriate to call it out. If the study truly wasn't able to find any correlation (positive, per my hypothesis, negative per yours), then either there really isn't any correlation (meaning all of the potential forces that would cause a correlation happen to be perfectly balanced (which would be surprising to me), or there is something wrong with the study.

- To be clear, I don't think there is a causal relationship between violent video games and violent behaviors.

- There are likely correlations between video-games and ADHD, as well as single-player video games (actually any solitary activity) and depression. There are links between both of those and violent behavior, particularly self-harm.

Not only. Eg in Germany there's long been an enormous stigma against violent video games. I haven't talked with German gamedevs for some years so maybe this loosened up since. But basically, if you worked in gamedev you preferred to tell your neighbours and acquaintances that you work "in IT". If they would find out you work on video games they'd pretty much fully cut you out of their lives.

(Note, to my anecdotal experience this is a purely German thing. I don't know other European countries where the same stigma exists)