OTOH, there is a strong argument that the Cessna SIDS are gold-plating in a deliberate effort to get rid of a lot of elerly aircraft.....rather like the British government gave a huge (on paper!) cash incentive to owners of perfectly usable older cars, to scrap them in favour of a relatively short-life "economical" and "low pollution" new replacement.
I have followed the ridiculous seat-belt farce,as a prime example of a huge con and rip-off.
So, yes, some wiggle-room is available without unduly compromising safety (C of A - V- Permit machines? ) but there is a sensible minimum, beyond which one should ask "fi it sounds too good to be true, perhaps it is? "