Who said anything about duty? :-)))
My point is, what are we going to replace those with? Especially leather & co. They have real life applications, they're not just fads. Plus, will those replacement products be sustainable? Vegan leather is just rebranded plastic, for example.
I'm equally curious, but I don't know the numbers, if replacing plastic packaging with paper/cardboard is environmentally sound. I remember back in the day efforts to reduce paper consumption, I think our sustainable paper production capacity was near its limits.