Could hauling as part of your job and just general hauling be separated? Specifically for Farmers and Trappers, I wouldn’t mind if they put up their own products, but letting them haul general items reduces their productivity. The farmer will let crops rot to do other tasks, and the trapper neglects his duties. It would be preferable that job related activities were always prioritized, too.
If you turn hauling off for them now, the farmer just dumps all the crops on the ground, and the trapper collects items until his backpack is full and then dumps them at random on the ground.
The game is still assigning excess haulers, too. The updates with the pathfinder are much better (not perfect, but at least 80% of where you would want them.)