This is my uneducated opinion based on personal experience.
I believe one way to reduce your reaction time is continuous repetitive practice.
When I was in the Army they used the Crawl, Walk, Run method of training.
Do it slowly and correctly over and over again until you can do it fast and correctly.
On the south side of Colorado Springs on the east side of I-25 just before the South Academy exit is a substation that's a mile around the perimeter fence.
I was supposed to walk around the perimeter of the substation every other night and check it.
I put the time to use by practicing my four-point draw. 1,2,3,4- 4,3,2,1.
I probably repeated it 50 times a night. Never fast just by the numbers 1 2 3 4.
So, one night I walked out of my house and I was walking over to my car to get ready to go to work and there was a gunshot in the back of the parking lot. I drop down behind a car and
then I realized I had my gun in my hand.