A modern V8 is absolutely fine with lower octane fuel. Massive improvements in fuel atomization, compression chamber shape, ignition timing, valve timing, air routing, cooling, basically literally everything about a combustion engine means that we can run a 5 litre V8 with an 11:1 compression ratio on 87 and make ungodly amounts of power.
The reduction in required octane is directly related to the fact that old V8s that had garbage compression ratios and horrible fueling got muzzled by emissions regulations so they couldn't compensate for their mediocre engineering by just dumping extra fuel into the process. All those things listed above that are meant to improve resistance to knock ALSO bring way more efficiency, and the interesting thing about gas engines is that higher efficiency often means the specific output is boosted as well.
Higher octane ONLY means a higher resistance to knocking. If your car isn't fighting knocking already, that won't improve anything. We could reduce the octane we require and get somewhat cheaper gas, but it would most likely also reduce the power output of the engine (fine nowadays) and the fuel economy (very not fine for most people).
Driving a truck up a hill is not a normal use case. Driving a luxury car is not normal. Driving a sports car is not normal. These are all specialty vehicles.
Normal cars do not need high octane fuel. Normal cars do not benefit from high octane fuel.
Car and Driver did a study of the effects of high octane fuel on a CRV, F-150, Charger, and BMW M5. Only the F-150 saw a >0.1s improvement to 0-60 time for high octane. High octane showed modest MPG improvements in some cases, but this were not enough to justify the higher costs. The CRV, the only remotely normal car in that study, actually had lower 0-60 performance on high octane fuel. https://www.caranddriver.com/features/a28565486/honda-cr-v-v...
I'm not saying not to fill your truck up with high octane fuel. There is a reason to do that. But most people are obviously not driving that around to the grocery store or whatever - it's a specialty vehicle for your farm or work. There's no reason for anyone to fill up their normal, personal car with high octane fuel unless the manual says it's needed.
Says the Car and Driver study I linked to which shows that normal cars (e.g. the CRV) don't experience improved acceleration or torque from high octane fuel.
The reduction in required octane is directly related to the fact that old V8s that had garbage compression ratios and horrible fueling got muzzled by emissions regulations so they couldn't compensate for their mediocre engineering by just dumping extra fuel into the process. All those things listed above that are meant to improve resistance to knock ALSO bring way more efficiency, and the interesting thing about gas engines is that higher efficiency often means the specific output is boosted as well.
Higher octane ONLY means a higher resistance to knocking. If your car isn't fighting knocking already, that won't improve anything. We could reduce the octane we require and get somewhat cheaper gas, but it would most likely also reduce the power output of the engine (fine nowadays) and the fuel economy (very not fine for most people).