My estimate is that 50% of UK pilots never get notams (from e.g. how many turn up at Shoreham not knowing the ATIS has changed) and I don't see why this should be very different abroad
There are whole sub-communities out there
Non-radio, non-notams, non-weather. I know a 2k hr pilot who cannot work out tafs and metars. He's a very competent pilot though.
The only opportunity to reach these people is on the 2-yearly revalidation flight, but that doesn't happen, evidently. I guess the pilot only has to say he never goes outside the local circuit, and that deals with that...