As well as reducing plastic usage in low value applications. It is sad, all the plastic litter in the world.
An waste industry buddy of mine designs landfills, and this is his take too. It's better to throw your plastic into regular trash (and other recyclables into the recycle bin), because then you at least know it's likely to end up in a landfill where it's safe, instead of being exported and dumped in the sea.
The ones that don't can be GHG emitters, but that just means there are less emissions somewhere else (where trash was collected from), because you just concentrated a bunch of matter in one place. It's not a significant net emitter.
I think it's more likely that regulated and aggregated pollution management will be at least somewhat successful. These plants will buy up vast sums of waste that would otherwise often get into the environment and oceans. Honestly with good air scrubbing it could replace many of our coal plants with better air quality outcomes.
Even pro nuclear folks will recognize that it has drawbacks and needs to be managed carefully. They believe that those drawbacks are less than that of fossil fuels and that nuclear can be ramped up faster than renewables.