I respectfully suggest that there has been more than just dumb good luck at play
It might also have something to do with pilots not particularly wanting to die, or kill others... maybe?
The Reno Air Races went five years without a serious incident... and then in 2007, blam! three fatal crashes. I hope you are not suggesting that these races, held in the most litgious country on the planet, were not the subject of intensive "risk mitigation" studies.
Perhaps the principles of safety have been around for considerably longer than the now fashionable "risk mitigation" process has?
I'm not suggesting that it is an innately bad thing to adopt these processes, but for goodness sake see them for what they actually are - a bureaucratic box-ticking exercise that keeps the lawyers happy and simply affirms existing best practices, while generating masses of largely superfluous paper.