Haulers of that type have a lot of upsides but they've fallen in and out of favor for perhaps as long as there have been motorcycles. They're a good solution for downsizing.
The primary arguments against are driveline wear and the potential for catastrophe if the bike should bounce into gear. Backing up can be "interesting" if it becomes neccessary.
I had one in the '80's and want another now.I never gave a rip about the driveline/tire wear issues. This isn't the sort of rig I'd haul cross country in the first place, but the potential for the bike to fall into gear is real. Most people who've used them at least remove the shifter when hauling so that there's no chance of a pothole dropping the bike into gear. Others remove the chain.