I'm merely pointing out that the people who think FSUs knew of all traffic were blissfully ignorant of the reality.
FSUs knew no more and no less than ATC currently do in the vast majority of unsurveilled Class G. In fact they would have known more than ATC currently do at major country ADs, due to the mandatory reporting requirements of AFIZs.
but I'm confident that there were exemptions for NORADO aircraft - e.g. gliders and aircraft without engine driven power sources - to operate in AFIZs.
There were indeed exemptions, however their operations were known to the FSUs.
Examples: An FSU would be advised by a club when gliders commenced and ceased operating, and also when (say) an individual glider from elsewhere was coming in.
Other no radio types wishing to enter or depart or operate in an AFIZ required an exemption (from Flight Standards I recall), which included specific timing and route to be flown, in a similar manner to how such types into GAAP ADs were handled.
In both these examples, FSUs would include reference to them in traffic information.
FSUs (and Briefing Offices at FSUs and at capital city GA ADs) aren't coming back, and I've always felt things went backwards when they were got rid of.