Interesting question.
I think it perhaps needs bearing in mind that legal currency minima are just that, legal minima.
Sometimes they get a bit absurd - for example I'm not currently legal to fly pax at night. I've actually done a reasonable amount of night flying lately, but each time I've taken off in the day and landed at night. So, I don't have a night take-off, and hence can't, within the 90 day rule, take passengers.
Alternatively somebody who flew three circuits, one at night, 89 days ago, can quite legally fly with passengers today or tonight, having flown nothing since.
So what does it come down to? Trained common sense I'd suggest. Anybody holding a flying qualification should be able to exercise enough judgement to decide whether they are current or not. The legal minima are a backstop intended to stop anybody being truly stupid, but we should all stop relying upon the black-and-white of the regulations, and apply our own grey matter to whether (within the regulations of-course) we are genuinely safe.
Problem is, regulators and insurers like black and white, thank heavens that most people operate within a club, school or company environment where there is a Chief pilot / instructor (or just somebody experienced and respected) who helps us all to display more than just blind adherence to the regulations.
G