Wow... The best thing I can think to say is: DUH!
I play MMOs myself. My wife does not. But we get along very happily. However, that also means I don't sit there for 50+ hours a week. I get on a few nights a week and enjoy my 'me' time. Ofcorse that also means I'm not playing 'hardcore' anymore... Been there, done that. The kids that live in their mom's basements can keep that crap. Too much time sink for a fantasy.
I've tried to get my wife to play, she has no interest. However she does enjoy watching me from time to time (especially if I'm going through some story-strong portions). But I have my me time, she has her me time. Otherwise we'd drowned each other. Did that in my first marriage. Live and learn.
What can damage your marriage? Anything and everything if the slightest bit of THOUGHT isn't given to it. Give me almost any item/task and I'll give you a way it can easily damage a marriage over time. Drinking Coffee even... If you're spending half your paycheck at joe's-coffee-shop, that type of irresponsible book-keeping over time and stress can easily damage a relationship.
Honestly, this type of a study makes me wounder who's dumber; the people being studied (no) or the idiots that think that it is a worth while topic to study (yup). What? You mean ignoring your partner over long periods of time could result in damage to the relationship? No (crap) Sherlock...
It's just like anything else. Learn to do it responsibly, and in moderation... Or it's your own fault for the consequences. That's just common sense to anyone who has any...