Legally, you have to have brakes for anything weighing more than 3000 lbs in CA. In many states it's 1500 lbs and above. I realize the blue hairs flat towing don't have this - mostly because the flat tow controllers are expensive and a pain in the ass to install. I can't say I ever drove a motorhome and thought to myself, "this has great brakes" - especially a V10 F53 chassis with a 4R100.
California Code, Vehicle Code - VEH § 26302
(b) Every trailer or semitrailer manufactured and first registered after January 1, 1966, and having a gross weight of 3,000 pounds or more shall be equipped with brakes on at least two wheels.
leginfo.legislature.ca.gov