Part of it is reflexes too. I used to love fast paced FPS games as a teen and was actually pretty good at them until my early 30's. As time went on, I started noticing I was doing consistently worse in 1v1 firefights. I started gravitating towards games that had a 'slower' way to contribute like playing vehicles in the battlefield series.

As time goes on I've gotten more and more into single player games, especially games that let me build stuff.