I actually wrote an entire post about the benefits of gaming here:
https://steemit.com/depression/@voltarius/can-a-video-game-save-your-life
I think honestly it's just that people are attracted to negative things. You always hear about the "bad things" gaming does to people because that's what garners attention, just like most news channels now are focused on negative events rather than positive ones.
Very true. My employer always tells me - you do something good, a handful of people get to hear about it. Do something bad and the whole world and their dog knows about it soon afterwards. Bad news spreads quicker :)