alt Hacker NewsI recall there's one factory on the planet still producing TEL, so once they decide it's no longer profitable it's over.
Aviation gasoline is probably the one market that still keeps it afloat, when/if piston aviation switches over the remaining market is small and insignificant.
At least in the US, the current proposed plan is to phase out leaded avgas by 2030: https://www.faa.gov/aircraft/draft_docs/draft_unleaded_avgas...