The Continental TSIO 550, is certified for 94UL. Virtually all of the IO 520 and IO 540’s will run on 94UL with low compression pistons, a 5 K mod. Yes there is a modest loss of power but in exchange you have fuel certainty for forever.
Instead of burying our head in the sands how about the alphabet groups lobby for a set in stone drop dead date on 100LL. If we said to everyone that only 94UL will be available as of Jan 1 2024, then everyone can plan accordingly and you have neutered the environmentalist.