when Elias tells Jon he worked as a filing clerk in 1972 he’s either giving a sneaky little hint or did a really funny mistake. But either way since Jon doesnt say anything this does imply that Elias can pass for being at least in his 60s or even 70s, or Jon had to think he looks younger than his age but didn’t have a reason to question it
i think a flavour of angsty jonelias i enjoy is jon being to elias, what elias wants to be to the eye. elias wants to be the ceaseless watcher’s special little boy. he’s so good and he’s so far from human. he’ll do anything for the eye. and he will take his place as its pupil. but he knows that jon, his archivist, is the true herald. the cumulation of centuries of planning. jon is everything to the eye, so he is everything to elias.