I'm 51 and don't yet experience reflex reaction issues, I do experience general energy/weakness issues when exhausted but when I'm rested I'm still fast and good to go.
So I think that there is a graduated process. Ride different bikes, ride differently, then when that no longer works, then quit.
You could still take handfuls of cash and go help out racers! Hopefully you will have disposable income in retirement.
When you can no longer walk to the track, then post on BARF. When you can no longer type then pray for a quick death.
Star trek:
Volcans, "live long and prosper."
Kingons, "live well and die quick.
I agree with Klingon philosophy.
The great question before us is not if God exists, or if there is life after death, or how did reality or the universe get created. But rather, is our brain the creator of consciousness or the receiver of consciousness?
I believe it is the receiver and that then opens up a great adventure a head of us.
I'll go one step further. I believe that many of the "fast" riders, pilots, racers, scuba divers, etc. living now, will be again together in 200 or 300 years as earth launches a fleet of ships, big bulky cement hulled ships with some amazing engines and then we will make contact with others and they will be shocked when we jump into their orbits.