If deficient plants have been operated successfully for this long, the implication to me is that their operators have proven responsible enough to handle it.
A lack of air bags is not noticable until your car crashes.
No, they are missing because the car had been built before the invention of airbags. It's uncontestable that currently operating reactors generally lack certain safety measures we'd have added if we built them today.
The question is if we nevertheless deem them 'safe enough'.
A lack of air bags is not noticable until your car crashes.