Obviously it's not strictly essential at all, given how many 10s of 1000s of years humanity survived without it - but once invented among a particular populatio

Obviously it's not strictly essential at all, given how many 10s of 1000s of years humanity survived without it - but once invented among a particular population I would think its usefulness (for various purposes) would be obvious enough that unless the raw materials become impossible to obtain, production would continue.