"We basically nuked a town with chemicals so we could get a railroad open"

[ProfessorGAC]

32. Not Accurate

I've been in dozens of large manufacturing facilities.
Heated tank cars are not heated in transit.

For high melt materials (like your sulfur example, or malefic/phthalic anhydrides) where boiling, hence potential overpressure, is not an issue:
The loading spots allow for preheating with steam coils. Then, they're filled. At the other end, steam is hooked up to remelt.

For things like sulfur trioxide & others with a narrow liquid range, electrical panels are sometimes used to ensure no overheating occurs. But again, they are allowed to freeze. It's actually safer to transport that way because it won't spill.
I participated in 3 incident investigations where small releases occurred but the standard was none. Every incident, no matter how minor, we're investigated at those sites. They all involved heated tank cars. There is no practical way to supply either heat or cooling to railcars in transit.

Perhaps they could do it in Europe where everything is electric so they have access to energy everywhere along the train.
But, I didn't see any such thing there either.

As to trucks vs. rail, the sheer structural demand on a railcar requires steel gouges thar have inherently higher pressure capabilities. In addition, I have not seen a refrigerated tanker truck, and my dad worked at a dairy.

Yeah, his truck had a reefer unit to get cold milk to the supermarkets but that's a different situation than a trailer.
I have seen trailers with heating panels to keep high viscosity materials from getting too thick. But, those use the coolant off the tractor, except in one case was a generator set was used in the winter, on each trailer. (The load has to be reduced by the weight of the gen set, so they were removed April through October).

It's much easier to put heat panels on a truck, run with electricity. In the case of cooling, we would need pumps and coolant, adding even more weight. (BTW, that whole application was not in hazardous service. The material was most closely related to a highly concentrated laundry detergent. Super interesting physical chemistry on that stuff.)

They make high pressure trailers, too. We've all seen them carrying propane, ammonia, carbon dioxide, liquid nitrogen, and the like. Since some of those are refrigerants, I'd think you'd agree it would seem silly to refridgerate a refrigerant!

As to the accident cause, I too have seen nothing definitive. It's just that history suggests that few rail incidents were unpreventable. But, it's certainly possible it's just random chance.