As I read,, I wonder why?
100 years of research,, and testing ,, with millions of trailers made of all shape and sizes and millions upon millions of miles on the road there is a reason why Wally built trailers along with all the other SOB company's with a 120v AC and 12v
DC systems.. It works,, gives flexibility,, and each system have a time and a place and reason of service.
What one might save on one end doing without will be lost on the other.. A converter is not a high dollar item,, and if the weight is an issue one can just scale back the size of the storage battery..