Once you factor in the time scales involved, your justifications for why plastic isn't much of a problem disappear. There is no significant decomposition of pla

Once you factor in the time scales involved, your justifications for why plastic isn't much of a problem disappear. There is no significant decomposition of plastic by microbes in the wild. Nature will fill niches but there's no evidence or guarantee that microorganisms will ever develop a significant and widespread enough ability to degrade plastic. There are microbes that literally eat rocks, but there are still plenty of rooks in the world. Nature developing this ability to a significant level will take a very long time. Plastics have been around for several human lifetimes and millions of microbial lifetimes and we only see hints. Even if we take an optimistic view, there will be multiple human lifetimes very badly affected by plastic pollution. We probably also don't want a microbe that is so effective at eating plastic, seeing how much we rely on it. At the first sight of a truly plastic eating microbe, manufacturers will start making plastic immune to organic degradation and the cycle starts again. Same with burning, you can't say it'd end up as CO2 anyway as one is an immediate effect and the other theoretical and very long term. I do agree that "energy recovery" as it is often called is better than landfill disposal but it is the lesser of evils. It's not always clear that not using plastic is a net benefit as its use might be reducing other environmental effects. In which case I agree that using minimal plastic and then using it for power generation is an option.