I've run (and am running) tires that are 40-50 years old. If they haven't been in direct sun their lifespan is infinitely longer. If there is no visible cracking on the surface, that indicates that the rubber is still pliable. We could argue that tire date coding is one of the biggest scams ever perpetrated on the public, but recent events have superseded that milestone. I go on a tire-by-tire basis - expiration dates are absolutely worst-case scenarios. If there's no cracking I would run them out - but then again I don't believe everything the government tells me and I don't have money to spend replacing tires that I have closely inspected and are still safely viable.
