sunfish this safety thing is such a pervasive part of aviation that you wonder why.
when you drive down the freeway at higher than suburban speeds I'll wager that you are never focussed on "safety", you are focussed on getting there without pranging or getting lost.
when you go out fishing in the tinny, you stow the safety gear under the seats so that you can get on with the fishing. you are focussed on finding where the fish are, not in drowning or "safety"
so why the great focus on safety in aviation? why not a focus on competent aviation?
I wouldn't mind betting that what is actually at play here is the fear of death.
some people succumb to the rituals of a religion to assuage their fears of the unknown. some people can never realise that while they can't see it because the air is transparent there are huge forces exerted on an aeroplane that will reliably occur if the speed is kept up.
biennials are more of a ritual to assuage the fear of flying than anything of real benefit.
on a personal basis I have no fear of flying. 40 years studying and playing with aerodynamics and a decade of aeronautical engineering study have removed my fear of flying completely.
lets just move beyond the BFR concept. the accidents still occur so what next?
will CASA require co pilots in every private aircraft because it is a demonstrated safety benefit in the airlines.
you have got to conquer your fear of flying or it leads to all sorts of nonsense ritual behaviour.