Tire dry rot is pretty common here in OK no matter the tire brand. The summer sun and heat which often exceeds 100 degrees, and hits 110 on a regular basis, can do them in pretty quickly.
For what it's worth, a project car I went and looked at a few years back (and did not buy) had 4 pretty decent tires on it. The car had been sitting for half a dozen years with one side facing the sun and the other side shielded to some extent.
The sunny side tires were at least moderately weather checked and on the shielded side it was barely noticeable.
On another note, I've seen some antique motorcycle tires that were in storage for 50 years and they appeared as new with zero dry rot and the rubber still supple. These tires were paper wrapped and of course had always been shielded from the elements.