This right here. If I lived almost anywhere else in the world I could get a 70 series land cruiser or Hilux or any number of others that are rated for 1+ ton capacity and 7700lb+ towing capacity, all while getting 20+mpg with a decent diesel engine. Instead, I'm stuck with some dystopian chicken tax + diesel phobic lunacy and end up burning twice as much fuel to tow or carry half as much. Idiotic.
E.g., Volvo XC40 T5 is 1600 kg in the U.S. https://www.volvocars.com/en-ca/support/car/xc40/21w22/artic...
but 2100 kg in the UK https://www.volvocars.com/uk/support/car/xc40/21w46/article/...
As I recall it has to do with standards for stability at speed...
All to say you can probably tow more than you think with a U.S. car that's also sold in Europe, just maybe don't go above 55mph...?
The only saving grace here is (a) the EPA doesn't actually enforce rules against diesel swaps, and most states tolerate it--some will even give you a new VIN! (b) nobody (law enforcement) cares about GVWR unless you're operating commercially or doing something obviously unhinged.