Very few piston airplanes above the entry-level and trainer fleet are normally aspirated. The piston airplanes that fly a lot (mostly in commercial service) are overwhelmingly turbocharged.
Those are the ones that need the higher octane fuel (and the ones that burn the most of it). I could have bought paperwork (the Petersen STC) to allow my Cessna 182 to burn alcohol-free unleaded car gas. That is not available for the replacement engine I installed in that airplane nor for my current airplane (nor any turbo airplanes to my knowledge).
Which is tiny; it has 115 horsepower for 5 minutes and 100 continuous. That’s still trainer and entry level or 2-seat Cessna 152 sized engine and about 1/3 the power of a modern single-engine Bonanza.
For what it's worth, some kit planes are now using the Rotax 915iS (Newer injected variant of the 914) for 4-seaters [1]. This engine puts out 135 continous up to 15,000 ft. For comparison, a given Lycoming 161HP non-turbo engine (requiring 100LL) shouldn't run above 75% continous (120HP), and can't put out more than this above 9,000 ft [2].
There certainly seems to be some innovation here, in this case driven by Diamond in Austria. It may have "helped" that Avgas prices over here in Europe are really quite high.
Those are the ones that need the higher octane fuel (and the ones that burn the most of it). I could have bought paperwork (the Petersen STC) to allow my Cessna 182 to burn alcohol-free unleaded car gas. That is not available for the replacement engine I installed in that airplane nor for my current airplane (nor any turbo airplanes to my knowledge).