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.