Notice how food storage boxes changed considerably in the last few years? It's because they're derived from shale byproducts that are essentially free, if not cost-negative.

There's an irony in that we have an overabundance of natural gas due to shale, but oil itself is becoming far less important to the plastics industry than ever before.

Related viewing: https://www.youtube.com/watch?v=pyfVTBI4dgA

I think plastics have been produced mostly from natural gas rather than oil for many years. Ethane & methane are an easier starting point for making polyethylene et al than the varied hydrocarbons in oil.