Because the chicken tax keeps out great vehicles so the US automakers don’t have to compete. The hilux and 79 landcruiser are run of the mill workhorses in virtually every country in the world except the US and Canada. They run rings around the Tacoma and tundra. Tariffs and old world protectionism like the chicken tax are keeping the US automakers on life support, but they’re all doomed - they’re not even trying to…
Toyota manufacturers those trucks in the US. They could manufacture the Hilux here too, but they choose not to. So it seems like the Chicken Tax isn't the actual problem. Toyota seems to think Americans do not want the Hilux, at least not in sufficient quantities to justify bringing it to market.