Wide spacing is primarily done so a lighter weight frame can be used. As the OP noted, it is popular in the ultra light class.
My concern on tight turns isn't the tire scuffing. But the added strain on the spring hangers. I have had these break on me on normal spaced/heavy framed units.
This is a major PITA. Had to go home empty, get my jacks, stands , welder grinder and generator to weld it up in camp, as the TT was not safe to move.
With the lighter weight frame, this is more likely to occur.
It is not something that happens over night, but overtime as the metal fatigues.
If I had one of these units, I would try hard to avoid sharp turns, and inspect the hangers before every trip.