Obviously, it depends on the game. Some games motivate you to complete all side/optional content, to catch all collectibles and to seek all achievements, but others simply don't. Considering these differences and the fact we play different kinds of games all the time, it's hard to give a generic and definitive anwser like "I complete more games now than before".
That being said, what I can say is: when I enjoy a game and feel motivated about its side content, collectibles and achievements, I usually complete it more than I used to do some years ago.
I think it has to do with maturity, maybe. When I was younger, even enjoying the game I didn't care about anything more than completing main stories and jumping to next games. Now, I feel pleased to live the game, to going deep in its universe, to understand and to learn with its storytelling, to appreciate the full map's design and artwork etc. That's the main reason I complete more games nowadays than I used to do before.