For curiosity’s sake, Ocelot was born in 1944 on D-Day, on the beach of Normandy, lol so in the mainline games:
MGS3, 1964 = 20 y/o
MGSV, 1984 = 40
MGS1, 2005 = 61
MGS2, 2009 = 65
MGS4, 2014 = 70
The majority (and prime) of his career in espionage is all offscreen, mostly between 3 and V while Big Boss is, ultimately, spinning his wheels on MSF— and then between V and MGS when presumably he was working with BB (as a sleeper agent for the Patriots (but really loyal to BB after all)).
This topic had me thinking about how the retcon of bossfight_cowboy into the lynchpin character only works so well because Lee Van Cleef’s iconic appearance is as a grizzled older man, so Ocelot could have importance written backwards in time. It’s a kind of serendipity that Kojima would I’m sure be so happy to hear called Lynchian.