I was rejected for aircrew training on eyesight grounds in 1964, which is how I initially became a Rockape. When I applied for nav training in 1968 I was accepted, even though my eyesight was below the standard normally required. As I spent most of my time as a nav staring at an H2S screen less than 3' away from my nose it never presented a problem!
When I was luckily enough to get a ride in a Lightning T4 I was somewhat surprised to see the pilot complete his start up checks and reach into his pocket and put on a pair of aircrew specs (not sunglasses). Somewhat spoiled the "steely eyed fighter pilot" image, but he seemed to manage ok.
At the age of 60 I passed my flying medical for a PPL with the stipulation that I wore specs when flying (and carried a spare pair). I was surprised to discover that eyesight requirements for a PPL are somewhat less exacting than for an HGV licence.