Are addictive computer games isolating people? Why?

I don't think so. I think there are a good portion of people who are already "isolated" so to speak. By isolation, I'm going to take you to mean "antisocial." Many gamers https://foreignpolicyi.org/best-free-pc-games/ tend to be pre-disposed towards that type of behavior or a social behavior. If the former, there really is no way for you to fix that in the first. If the latter, then it doesn't affect their social life and they balance that very well (or even combine the two!)

Aside from that, it depends. Is this person playing video games at the detriment of his/her mental / physical health? Is he/she playing with others? Is this multi-person play colaborative? Competetive? Violent? Peaceful?