>>62084You have a false dichotomy in this thread. Reaction time (what you call reflexes) always corresponds to general intelligence. In fact, reflex timing is the one way to have a cross-cultural iq level that doesn't depend on education. In other words, working on your reflexes will help your cognitive ability. Furthermore, the older you get, the more pronounced the effect is.
https://pmc.ncbi.nlm.nih.gov/articles/PMC5608941/#:~:text=Highlights&text=Both%20simple%20and%20choice%20reaction%20time%20are%20strongly%20correlated%20with%20IQ.&text=The%20correlation%20increases%20with%20age.&text=The%20underlying%20relationships%20are%20different,is%20complex%20and%20non%2Dlinear, I'd say the great Metroid-Vania style games would keep you sharp without being board to death. Especially the main two, Super Metroid and Castlevania SOTN. WarioLand 3 is one of my favorites. That one has some great puzzle solving in it Metroid requires you to recall areas that you couldn't visit before because you lacked the power-ups. Getting one always triggers the memory of that area then you go back.
Personally I believe the best thing to stay sharp is to master different games. It could be anything, a platformer, shmup, puzzle, strategy game or whatever. Old games are very much about repetition and are short; try to overcome them without using features like save states or rewind, without worrying about finishing, just play them. Once you get really good at something, move on to a different game, And yet I specifically suggest a forgotten game called Locomotion (Kingsoft) A good mental workout, I don't think the premise is that accurate. On the surface it might seem a puzzle game is more about problem solving and cognitive skill, but there's no reason to elevate it above others.
Most games that you think are about reflexes are a combination of short-term decision making (problem solving), long-term decision making (strategy) routing (memory), and fine motor skills. I'd even argue the average arcade game is almost an optimal brain workout. Elon Musk said recently that he judges how sharp he is during the day by picking up one of these games.