2 Separate Blowouts on RV Yesterday. Learned Important Lesson on Tires

Used to be. Out in farm/ranch country Missouri. they would run 8 ply on their pickup till almost bald, and then run them on the stock trailer till they blew or come apart.
The last 10 years I worked (till about 2017) in town, I drove30 miles one way always on plenty old and plenty used tires , usually on a Duster and some on an old little Ford Ranger. Never had a flat or one fail. Go figure.