What a typical time is
In a large study of simple reaction time (Woods and others, 2015), the average was 231 ms, or 213 ms once the researchers subtracted the delay contributed by their own keyboard and monitor. The spread was tight, a standard deviation of 27 ms.
Age slows it, but less than people assume. Der and Deary (2006) found about 0.55 ms of slowing per year of adult age, so four decades add roughly 22 ms, which is smaller than the ordinary difference between two people of the same age.
Your hardware is part of the number
A touchscreen adds about 50 to 100 ms of its own latency before a tap registers, and a 60 Hz display can hold a frame for another 17 ms before you see it. The same person therefore tests faster on a desktop with a mouse than on a phone, and a fair comparison uses the same setup each time.
What matters more in a fight
A duel is reaction time plus the movement that follows it plus the click. Reaction time is the part you can change least. The movement is trainable: a cleaner flick reaches the target sooner, and good crosshair placement removes most of the movement before the fight starts, whatever your reaction time is.