That alone wouldn't be able to account for it. The Model 3 would need a fatality rate about a third as much as that of the Model Y to pull the average that far, seeing as the Model S has a fatality rate close to the Tesla average, and the Model X is very rare compared to the 3 and Y.
more chance of peanut butter interfering with critical touchscreen controls.
Actually, I wonder... if a car is safe and avoids many accidents, could the unavoidable accidents be worse overall?
Kind of like a drug that cures disease #1 blamed for causing disease #2... but actually the drug worked and the next statistical thing to die of after #1 was #2
Those aren't touchscreen buttons --- they are on the steering wheel or yoke. On the current Model S and X they are capacitive buttons but there's a homing tab so you can find it without looking at it, and there's also haptic feedback. On the new Model 3 iirc it also physically clicks when you press it, although the lights and rear-facing camera button are capacitive.
The only "critical control" that is on the touchscreen is choosing whether to go forward or backward (aka shifting into drive or reverse), which can be done on the touchscreen on the Model S, X, 3, and Cybertruck. Of course, this is typically only done when the vehicle is stopped, so it's fine. There are also backup physical buttons in case you can't use the touchscreen.
My guess is that is due to higher average occupancy for model Y vs model 3.