So, basically '60s Formula 1. Might be fun to watch. We'd certainly see some crazy engine designs and a lot of re-fueling pit stops...
This is not accurate, the first production direct injection gasoline automotive engine was in the 1954 Mercedes-Benz 300SL. It's true, you probably won't be running piezoelectric injectors without computer controls, but there's nothing preventing direct injection.
But that would make it interesting. How many of the advances we've made in the past 75yrs could be accomplished some other way if you take the computer away? You don't need a computer to accomplish nanosecond timing. Maybe there's a clever analog way to run piezoelectric injectors.
I want to see F1 car design be about function/performance above all. I want to see awesome gadgets using insanely clever design. Then ideally that design should influence built items in the rest of the world.
F1 used to be influential in creating and developing high technology. Now it seems to be about gathering high technology from elsewhere so as to meet the insane regulations most efficiently.