Gaming requires just as much skill and mental focus. Gaming is incredibly competitive, just as much as any other sport. I guess it all just depends on what you want to make the definition of a sport. Does it have to involve physical movement?
Playing video games teaches you how to do stuff like promblem solving or math or it teaches you the defination of words that other people wouldnt know .
If poker card games and chess both have the players sitting down and are considered sports, why not virtual gaming as well. There are two kinds of sports: one physical and one mental. There is no good reason to debunk virtual gaming as a sport, and I believe the participants of such virtual PvP events have the same mentality as physical athletes.