I'm gonna use anime as an analog here- I was a huge weeb in high school/my 20s, and amassed at least a thousand anime DVDs. Now? It's been years since I sat down & watched a show through, and I've sold off something like 70-80% of those DVDs. It would seem like I've grown out of anime.
Thing is- I don't really feel like I have. I still like it, I just tend to do other things nowadays. I think two things happened: 1) You know how they say "90% of media is crap?" I feel like I burned out on sub-par shows, so even the good stuff doesn't spur me that much anymore. As I've cut away more & more of my old DVDs, leaving a much more concentrated collection, I start to feel more inclined to watch something again. But, that I think is dependent on 2) most of my anime-watching friend group either lost touch or fell out of it. Having people to bounce interest & discussions off of definitely affects fandom. Losing that support definitely effected my interest. If I met some few friend who was still firmly entrenched in the otaku lifestyle- yeah, I'd totally fall back in.
Right now, I sit with my game collection where my anime collection once was. I just passed 1,000 games at the end of last year, I hit up 2-3 local cons a year, I play with my friends- if my current group shifted to non- game players, there's a good likelihood I'd be doing a similar purge to my games. I could also get comfortable playing one or two select old favorites & decide to drop the extra stuff in favor of a handful of 'comfort games'. But even if I moved away from the heavy-duty gaming & collecting I do now, I don't think I'd ever lose interest entirely. Much as I still know the titles of the big anime today (even if I don't watch them), I think I'd keep tabs on the gaming industry, even if I wasn't playing.