Well Paul,
might be in the US and there about.
Over in some countries in Europe operators have a different approach.
After the deliberate flight into ground of the AirBerlin in France, because medical issues weren´t looked after, the operators are careful who to employ.
Nobody want a crash - but if one happens and the board finds out, that the pilot had problems with the vision, they might get hold liable.
I doubt, that in some/most european countrys you would get the appropiate 1st class medical today.
Times change - what was possible yesterday and might get still signed today by the doc, you know for thirty years, could be impossible if you start into the buiseness.