I would say it is likely that importing it would be the most cost-effective option, so it’ll still be used heavily. I imagine it’ll only fall heavily in usage if its manufacturing is outlawed in the places where importing it from would be cheap. I think that is pretty unlikely.

And if production is banned, industry is going to likely want to find something else to do with the input materials, which could easily be exporting it to where the production gets outsourced to.