i picked up one of the more technically demanding characters in guilty gear xrd (ramlethal) at the tender age of 39, after not having played any fighting games for maybe a decade and having never played guilty gear before. i was slow af when i started playing again. i felt like i couldn't do any moves and my reflexes were trash. but as i played more i became acclimated with the speed of the game and learning combo and link timings. the game "slowed down" which effectively sped up my inputs

you can get good at those games but it takes time and practice, and it takes more time the older you are, depending on your history with fighting games. i had a good base of thousands of hours logged in arcades on xmen vs street fighter, marvel vs capcom 1 & 2, and various others but that was literally 20 years prior. i really felt like i had hit the reset button since i hadn't engaged with fighting games since the early days of street fighter iv. but i kept at it and i got good at fighting games again. it took forever but it did happen