Depends on the subject in question, and what people are arguing about exactly. If the argument consists of, "Man I wish they would implement so-and-so because the game would be much better, since I enjoy spending my time with it, it's really starting to get on my nerves, and I wish they would do it soon." - Then that's a pretty valid argument, worth arguing over.
However, if the subject is, "My life is severely affected by so-and-so feature/bug and all I am is pissed off all day about it, and I'm in a fit of rage and want to cut myself, etc, etc." Then "It's just a game", may 'just' apply here..
However, if the subject is, "My life is severely affected by so-and-so feature/bug and all I am is pissed off all day about it, and I'm in a fit of rage and want to cut myself, etc, etc." Then "It's just a game", may 'just' apply here..