What would help is to develop a material that is just as good as plastic (or better), degrades easily and is cheaper as well, and then wait for them to copy. Germany basically did this for solar energy.

The point of plastic is that it doesn't degrade. How could you make a bottle that maintains its integrity when storing lemonade but dissolves once it hits the ocean or a lake? There is no useful signal that separates the situations. You could try continuous disintegration, but this requires people accepting part of a dissolving bottle in their drinks.

Such as biodegradable plastics, which can, in some cases, fully decompose in as little as 24 months![1]

[1] https://en.wikipedia.org/wiki/Biodegradable_plastic

I think the issue is no matter what policies are adapted outside of Asia, the current status of ocean plastics will remain until Asian countries modify their internal policies.

We could not send our recycling to Asia to deal with and build plants to process it here at home.