Well on the long run they tend to make you feel more lonely and try to avoid being with people except if it were handled the right way .
It depends on the kind of the game too so if we are talking about a battle royal multiplayer game it tends to make the player nervous both when playing and when he is just living his normal life why? Because it is very competitive
On the other hand if you are playing these game with a team it can make your teamwork better (that doesn't go against that there should be a limit for how much they use their gaming gadgets for)
