The definition of "art" is not "hung in a museum". The people who hang art in museums would tell you that. So the real question isn't whether video games are art, but whether they can address the kinds of questions addressed by other forms of modern art (and do any do that well enough to be considered for inclusion in modern art museums, alongside other works of concept and technique).

This is aggravated by the mutual contempt between the "art" and "engineering" camps, with each finding reasons to look down on the other.