Not much is left.
I made a game of it one year when I was single. I heated with wood. This also handled all my paper waste. Vegetable matter went onto the compost heap. Meat, fat, and most bones went to the dog. I didn't buy stuff in tetrapacks. Polyethylene is essentially a heavy wax, so with care to do it with a hot fire, it could go that way too. So my waste stream was about 1 bag a month -- more in summer when I didn't use the fire. Some plastics I wasn't sure of, glass jars, a few tin cans lid ends from frozen juice.
Some years ago in an oil field in, I think Oklahoma the engineers of the field collection network heard that PE didn't degrade. So they made the network out of PE pipe. MUCH easier to work with than steel. Three years later the pipes were failing -- oil field had a bacteria that thought that PE was a good source of energy.
I told this story to my brother, who is a professional microbiologist. "Sure," he said. "If there is a chemical reaction that produces energy at reasonable temperatures there is almost certainly a bacteria that will exploit it." I refer to this now as "Skipper's Law" Not always easy to find the bacteria that will do what you want.
The problem of waste is one of economics, and is fairly easily solved.
A. Require companies to accept their own products back for recycling. This in effect requires a reverse distribution network. It is now to the companies advantage to make products that can be easily recycled at a place closer than the factory. They then contract their recycle obligation to a more local source. This hits products such as tetrapaks hard. No one is willing to take them apart. I suspect that these would quickly vanish to be replaced with plastic coated cardboard, using a plastic that was easily burnable.
B. We used to recycle bottles. Beer bottles in particular were universal, and made 6-12 round trips before getting lost or chipped. The introduction of the long neck, then fancy shapes, and colours made this more difficult. So this problem can be solved in a different way with a tax incentive. Create a set of categories (dripper size, beverage, soft foods, hand access) and sizes. The most popular of each container gets the lowest tax. Something like 20c/liter base charge, then 10R^2, where R is the popularity ranking for that category most popular, rank 0, next most rank 1. A company that uses a custom bottle now has an absurdly high rank, and pays an enormous surcharge.
C. Everything is barcoded or rfid coded or taggant coded with the part and material. (A taggant is a tracer added to explosives. It consists of a thin chunk of ceramic coated with multiple coloured glazes, then ground up. The glazes aren't harmed by the explosion, and they can be easily sequenced with a microscope. Should be ammenable to robot sorting.) Fluorescent dyes could be added to materials. this allows material to be sorted by their fluorescent spectrum under UV scan.
D. Robotics, and machine vision. Clever machines can sort most of the material.