So what does that mean for US companies sending packages into countries that are part of the UPU (Edit: virtually all countries on Earth)? Can each country now refuseand set their own rates for transporting US parcels the last mile?
Probably, since everything is bilateral in agreements and negotiations. The point isn’t to minimize costs but to even out the playing field. US companies drop-shipping overseas will likely pay more, but that’s a consequence deemed overall worth it for the US local economy and market.
Last I ordered in the US (to Denmark) I paid 30USD flat fee for custom processing... On top of shipping and customs. (On an item worth 20 USD)