I hope people aren't counting on playing games that require fast reaction speeds. If your jam is turn-based games you're in luck, you should be good to 100. But, if you're a competitive online gamer, you're in for a rude shock if you think you're going to retire and compete against the 20-somethings.
It's not just reaction time that interferes wirh us old folks gaming, it's developers insistence on making game mechanics as uncomfortable as possible. I just don't have the stamina or flexibility to spend 15 minutes fighting some insanely difficult boss fight over multiple stages while constantly mashing buttons.
I think there should be an "Experienced gamer" difficulty level where the rest of the game is normal difficulty level, but the boss fights are less of an endurance challenge.