Camber angle on a two-wheel trailer?
Tyres wear a heap faster when they're not square to the road surface.  For example, tadpole recumbents wear out front wheels very fast.

Also, those riding bikes while towing trailers are going relatively slow.  I've managed to roll a kiddies trailer that was loaded with two landrover road wheels weighing 68 kilos, but that took a speed of around 22 km/h on a fairly tight roundabout.

Certainly it could work - you'd want wheelchair stub axles and mount the receiver tubes at a slight angle.

Downsides, your wheels would suffer from sideways stress toward the middle when travelling straight and standing still.

Also, the wheel bearings are going to be under more stress all the time too.

Racecars and race wheelchairs are about performance, not longevity, so a different set of requirements.