A way back (this thread is building so fast I can't now find them) a couple of posters asked whether NATS was taking over the "decision process" from those normally in command of aircraft (pilots) and making fly / no-fly decisions.
The answer may very well be "yes" to that, but then it's worth remembering who owns NATS! Answer - the airlines. I would propose that it's much easier / acceptable in
PR terms for the airlines to have NATS make a no-fly decision than make it themselves.
Rather than them (BA / Easy / Ryan etc) saying "it's not a good idea to fly due potential a/c damage / risk to humanity etc" surely it's easier to say "the authorities shut it down."
There's no implication in this that it's not the right decision, but in
PR terms it's far, far easier for the carriers. I know - I worked as a
PR man for 45 years (not in this industry tho')!