Don't be so utterly ridiculous. Most people have no idea how to deal with a
trailer and will probably crash. In the UK it will limit their motorway speed
to 50 mph IIRC.
Maybe Europeons would crash. I've dragged a U-Haul (known in the US
for renting garbage) trailer exactly three times, once last year
(650mi) and once a couple of weeks ago (850mi). No crashes, nothing
even close. Pulling a trailer isn't rocket surgery. Even backing
up can be done by anyone with a little patience, practice, and
practical physics (can't push with a rope, type).
I limited my speed to 75MPH. ;-) It didn't try to go faster than
my truck, even once.
It's a totally fatuous idea.
It is, but safety has nothing to do with it.