FWIW - on my '93 Pathfinder, I replaced the 31-10.50R15 tires - which wore out before they aged out - with a set of General Grabber 265/75R15s.
The old tires, which had a square-shoulder profile, would follow highway ruts and had a fairly harsh ride.
The new ones addressed both issues, and at .40 less OD & tread width, no negative influences; as an added bonus, less expensive, too.
(I don't drive it on sand dunes or rock-crawling or anything that requires the flotation tires.)

I was going to mention the Leno article.
I replace them when they're worn out or show signs of age.

When I bought my Barracuda, it had Goodyear wing foot radials on it. They were 23 years old but still looked like brand new with nearly full tread. I D.Q.'d them and put B.F. Goodrich radial T/A's on it, since I plan on driving it.

Bought these wheels & tires new in 1985.

Still use them in 2023 ....LOL

This article was written for motorcycle tires, but rubber is rubber:

https://www.revzilla.com/common-tread/debunking-the-tire-age-myth

Once I start to see dry rot on tires I typically replace them, especially for my motorcycles and my Fury.

The tires that were on mine are about 15 years old, maybe more. And always stored indoors and on carpet before I bought it.
They looked like new and drove perfect


When I switched mine to redlines radials. The old tires went on the other car

Would I take them on a across country trip, No
But have no fear to drive on them around town