Manufacturing is and always has been a complicated one. Until there is some global emissions tax upon products that factor in full material to consumer aspects from production and shipping emission - things will never change and the ability to have a local product cost 2x more than some imported one that has 10x the emission, is still going to play out until there is a true emission tax (not just carbon). Hence the whole emission/environment and humanity impacts of industry has no true global standard and the variance of those standards is a difference that we all end up paying the difference, albeit indirectly.
Hence you get workarounds happening like the example you mention about chicken tax - https://en.wikipedia.org/wiki/Chicken_tax workaround that can play both ways, yet if there was a base-level standard and measure to balance things out, then such loopholes become less harder to happen, or needed. Alas the only common standards are weights/measures and currency, everything else does vary.
As an aside, I dare say that the history of importing chickens into Europe is more fascinating than most imagined, and one that still plays on even to this day.