I'm 34. I think anyone born in the 80s or 90s games to some degree even if it's just a casual iphone or smart phone game once in awhile. Just that generation or generations.
The cool thing about gaming is stupid little moments like playing Mortal Kombat X against your fiance and laughing your ass off, or having your kids play Street Figher and your directions help them learn how to do a hadouken, or them getting thru various PVE stages on Destiny on their own. Kind of awesome seeing them get all excited about things that come natural to us "old timers". Kind of the same reactions I got when I was playing in the arcade many years ago.
Gaming isn't about age to me. I do think that certain groups and certain games gear to certain age groups but beyond that everyone games nowadays or almost everyone.
I do feel that the newer generation is geared more towards iphone, Ipad, and portable gaming then playing on a system. I could be wrong but thats the vibe I get from casual people aged 5 to 25 or so. So it kind of makes sense that most moderate to hardcore gamers are 30+ cause we grew up on systems and PC. I feel we prefer more of an "arcade" experience.
IDK I could be wrong just my two worthless cents lol.