It depends....
Below is a tire that was 8 years old, BUT the car had sat. Outside. With that side exposed to the sun.
When I bought that car, I checked tire pressures & fluids and headed home; the result below happened 100 miles later. Could have been disastrous. Sounded like a couple rocks popping out of the tread at 75mph, then it BLEW 3 seconds later.
A car that sits inside, out of sun / ozone, I MIGHT consider 10 years for local use, with frequent checks. If I'm going to travel, nope, 7-8 years is it.
I had to replace tires on the 86 Saleen last year after ~12k miles over 9 years and 100% indoor storage (with 75% tread remaining). Had a roundtrip drive from Kansas City to Albuquerque. Just not worth the risk. Same situation coming up next year with our late-model...