Hmmm... I have an interesting perspective on this. I played all the time when I was a kid. That meant taking $5 and going to the arcade during what I consider to be the peak of arcade gaming (around 1980 or so). I still remember fondly "Top 40" songs like Another One Bites The Dust playing while I played Zaxxon (whose graphics utterly blew me away at the time), Donkey Kong, etc.
I also had an Atari which I played quite a bit. But I got bored with console games because they were so shallow (no saves) and didn't hold up to the arcade games in terms of graphics/gameplay.
Once I hit high school and college I pretty much stopped playing games entirely except for the occasional RPG on my original Mac (things like Wizardy, Might & Magic, etc). I also played stuff like Rogue and XConq on the university computers. Note, also, that this corresponded to the video game crash of the mid-80's. I guess I didn't really notice that crash at the time because I had pretty much stopped playing before that happened anyway just in becoming a teenager. Of course, things are very different now and were I teenager these days I'd probably have kept playing - what with all the online multiplayer and such the kids enjoy these days. When I was a teenager, even
using a computer was considered the heights of nerdliness. I still get a kick out of seeing anyone and everyone now with a laptop computer and everyone using Facebook, etc and shake my head at the insults and nastiness that went with that back then. I think the people who are my age that felt that way then should be banned from using the Internet/Facebook/etc now

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Anyway, back to my late teens/early 20's: being very very busy then (school, fraternity, and University club volleyball team early on, then a steady girlfriend, followed by graduate school, marriage, etc) I didn't play all that often. At that time arcades turned into all fighting games and I really disliked those. I know a lot of people on CAG love the Street Fighters and Mortal Kombats and stuff, but to me that was the death of the arcade. The last arcade game I remember putting any serious time into was Gauntlet. Also, for most of my 20's, I played a metric ton of (real) basketball. I used to play every few days for 3-4 hours.
I think it is really funny the OP mentions the "golden PSX/PS2 era" as I sat that out entirely. I had an NES and played Mario and Zelda a bit when I injured my knee and couldn't get around for a few months. But, to be honest, while they were a great improvement over my previous system (the Atari), I didn't think they were all that great and I never really got back into console gaming except for that couple of months in 1988 or 1989. So I missed out entirely on the SNES/GenesisN64/PS1 era. That era, to me, is a void - a black hole. It holds no nostalgia factor to me whatsoever.
I got back into console gaming when I had kids, interestingly enough. We got them a Gamecube in 2003 and I've been into it full force since then. One of the first games I played was the GC Star Wars Rogue Leader game. That thing BLEW ME AWAY! I couldn't believe console graphics could be that amazing. I'm telling you - I really didn't pay attention for about 15 years there. But
that game was the one I always dreamed of when I was a kid. So that, along with other stuff like Super Mario Sunshine, got me back full-force into console gaming (and for that reason, I consider SMS to be the best Mario game which I know is a very minority position!).
Now I play WAY more than I did in my 20's and probably even more than I did when I was a kid. As Hell Monkey says in the 3rd post, it is because I don't have all the other "hobbies" I used to have. Plus I play with the kids now - so I have some time playing with them (LBP2, Sonic racing, etc) and some time playing by myself (Dragon Age, Mass Effect 2, etc) when everyone else is asleep.
So, yeah, it may seem when you are in your 20's that maybe your interest decreases. I think that is normal. But it will pick up again when you have kids and the new systems then are light years beyond what you played when you were a kid. In fact, I recommend taking a break if you are at all bored with gaming. You'll come back later with renewed vigor

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