I would argue it's a side effect of getting older.

Not that you're growing out of games, but moreso that you're spending more time working, and doing other life related things that gaming no longer feels productive of fun.

I'm working full time and take online classes, but I really love gaming still, I've just had to find games that respect my time, since my time is so precious to me right now.

I've grown to loath multiplayer match-based games because it's the same thing over and over again with nothing to show for it, while things like DOOM, Skyrim, Dishonored, older assassins creed games, and various indie titles are all quick, fun, to the point and offer good stories that I enjoy.

I just can't deal with round after round after round of the same thing. Or an MMO where it's just "Do this for hours and hours to grind out this skill and that skill"

Like I want to play the game, not click 30,000 times.