this is good, but I think we should build our own (illegal) stonehenge. Or maybe a pyramid. Not only it'd be nice to have something other than microplastic standing after the society collapse, it'd be a huge powerplay. As we seem to be wanting to join earlier civilizations that are no longer here (nor remembered that fondly) it seems only adequate.
My geographic area doesn't really have stone available, best I can do is a mound :(
I don't think that's how it works. Plastic degrades fast (especially with UV radiation), it just doesn't fully go away. That's how we get microplastic and harmful chemicals everywhere.