To answer the OP:
How much of being a fighter pilot do you believe is genetic?
None of it. Had plenty of students in training with quite a bit of talent, or even natural talent, who washed out due to two problems:
1. Inability to learn quickly
2. Failure to work hard.
Had a number of them surprise me by earning the chance to fly jets and succeeding when I wasn't sure if their talent level was up to it. (Good on 'em!)
Caveat: There are some fine potential fighter pilots who never got to fly due to anthropometric* limits (which has to do with "what part of your body will you leave behind you if you have to eject" and "can you reach that switch under 6 gs?")
*Thanks langley, oops!