Society flourished without lots of stuff we have today. It just flourished less.

And people aren’t failing to migrate away from plastic because “somebody would make less money”, they’re using plastic because everything else basically sucks in comparison. It’s tough, cheap, light, stable, easy to shape, doesn’t often break dangerously, can have all of its basic properties modified, and more. Nothing else is THAT good.

Edit: Not to mention, it’s not as simple as “don’t use plastic packaging anymore”. We pull oil into a machine and cook it off at various stages to produce various things. Turning cooking stage 8 of 12 into a worthless pile of garbage to be discarded doesn’t stop us from pulling in that oil for the other 11 uses.