Second guess on tires:

Wheel size was running 13, 14 & 15 for years. Don't know why or who "standardized" it. Ford tried the 390 mm wheel, which was 15.3". (TRX program on Mustangs in the mid '80s.) That failed.

Anyway, since the wheel size was hard to change but the width sizes are easy to change, my guess is the compromise was reached based on the "what's easiest" basis.

Just a guess. I didn't go google it, because frankly, I don't give a used 7.35 x 14.