There's some poorly run landfills, but how about we campaign to somewhat improve landfills instead of trying to reform all of modern society?
Also, you aren't thinking in deep time. Plastic waste needs to be managed indefinitely if it isn't going to be incinerated, because plastic becomes more dangerous, not less, as it becomes finer particles. Which also penetrate containment more readily.
We can regulate our own landfills and we can regulate which countries we export to. This is a far more realistic prospect than just banning most plastic products outright, as you suggest.
> Plastic waste needs to be managed indefinitely if it isn't going to be incinerated, because plastic becomes more dangerous, not less, as it becomes finer particles.
Yes, waste needs to be managed indefinitely, and we will always have to manage waste. We can do that.
How many years will it take until the plastic is no longer able to get into the food chain?