I believe heating caused by under inflation is the number one cause of blowouts.
@CapriRacer will know.
First, we tire engineers don't like the term "blowouts". The term is used in the public arena in so many ways, including times where the tire stays inflated.
The number 1 reason for tires being removed from service is they are worn out. I don't know what percent that is, but it's about 80%. About 15% of the tires get a puncture in their life, but most are repaired and will wear out.
But we're talking about RV tires here - and there are 2 groupings according to the way they end their life.
There's a group that behaves like other tires and then there are ST tires. For some reason that I don't understand, trailer manufacturers don't seem to learn the same lessons manufacturers of vehicles with engines learn.
What trailer manufacturers do is put the minimum tire size on. Further, they tend to buy tires based on price. So for a period of time, ST tires were manufactured in China when Chinese tires were just entering the US market - that is before they figured out how the game is played - and the way it is played is that tires have to exceed the government minimums by a substantial margin in order to perform adequately. Those Chinese tires performed pretty badly and where they were most obviously present was on trailers. It was a niche market that few tire manufacturers made tires for.
Further, ST tires require more inflation pressure than the light duty tow vehicles, so many of those tires were underinflated. The net effect was that there were many failures of the "blowout" kind and it was hard to determine if the cause was an inadequate tire design or underinflation.
But today things are different. The trailer manufacturers are doing a better job of sizing tires. The tire manufacturers are doing a better job of designing tires and users are doing a better job of inflation maintenance.
And even then, ST tires seem to be behaving differently. They aren't failing as often, but they are failing much later in life. What I think needs to happen is for trailer manufacturers to go one more step up in size. Better yet, go up 2 steps and use less inflation pressure so the ride is better for the contents of the trailer.