With China no longer accepting dirty recyclables from the US which are terribly hard to process we're probably on our way back to multi-stream recycling. Sad fact is that apparently the recycling truck is one of the worst causes of contamination when it compacts otherwise good recyclables. It's a bit more effort and a significantly higher rate of trash versus recycling, but in the end I think it would be worth it. Your idea has merit as well, though last I knew bioplastics still had some problems to solve in order to replace standard plastics, still worth pursuing.

Of course the somewhat simple alternative is to slightly change the consumer model, where you bring multi-purpose and longlasting packaging, they put the stuff in it. Dispensery type shops. That already exists in a few shops around Europe at least. You bring your container and fill it up with grain, liquids, whatever.

I can't really make up my mind on whether that would work for all food types. Maybe there's some heavily processed food that is dependent on being sealed until eating. I know potato chips bathe in nitrogen while sealed.