The problem is any idiot can make a bottle that lasts thousands of years. It takes an engineer to make a bottle that barely lasts a year.

Unfortunately, I think it's that either there's a microorganism that will eat your material, and you get a couple of years, or there's not, and you get thousands.

A milk carton?

Most tetra pak like materials and even aluminum cans are actually lined with plastic. Plastic is the greatest material ever, right until it needs to be disposed and then suddenly the biggest upside becomes the biggest downside.

Wood, cardboards, and papers. Unfortunately, they are not as easily shaped and more expensive to make. Figure out how you can mass produce an iPhone, including all the PCBs, out of wood and paper and you will become a billionaire.

Not really, no. For packaging type materials, either something will oxidize and is also water soluble, or it doesn’t oxidize and isn’t water soluble. Not much room in the middle. Making any paper based product last longer takes.. plastic.