X2 on 10-ply tires or more...
My OFF-ROAD POPUP TRAILER has 15-inch tires on it and high clearance. Couldn't get to a few of the places I like to camp at if I didnt have this setup...
Sometimes hard to cross that rock bed mountain stream up on the forest service roads sometimes without high clearance.... Beefed-up sidewalls also a must for us OFF-ROAD guys... My setup will literally go anywhere my 4X4 truck will pull it.
I guess it all depends what you want to do with your trailer setup
The down-under trailers is Australia have it figured out...
I would think there will be alot of things to consider beefing up the standard dual wheel setups on the trailers. Don't just go throw bigger tires on it without looking at all aspects.
Roy Ken