It sounds like you are somewhat blaming the "Made in U.S.A." component of the tire.
Have you looked a Goodyears website??
Check out this page
Tire Warranty | Goodyear Tires
From the page
"A tire has delivered its full original tread life and the coverage of this warranty ends when the treadwear indicators become visible (worn to 2/32"), or six (6) years from the date of original tire manufacture, or new tire purchase date (whichever comes first). (Without proof of purchase the date of manufacture will be used to determine eligibility.)"
6 years worth of warranty!!
How long is the warrenty on the made in china tires? I bet is NOT 6 years.
I bought new goodyears last winter after my old ones failed after 7 years of service. (Yes, I have my prooff of purchase.)
I do think you did one good thing, replacing D rated tire with E rated tires is allways a good idea. Every tire in that size I have ever seen is made in a load rating "E" . Personally I see no reason for D rated tires in that size.