I thought this was basically a non-issue as the battery circuitry would kill power before it got past that point. Or does that just stop it from emptying completely?

I think it depends on the application where the circuitry cuts off. Almost all applications will have circuitry that cuts power before the cell dies completely. You even have individual 18650 cells that have such a circuit built in (for flash-lights and so on)

But increased battery degradation starts way before you hit that limit. At least with cell phones, that tend to push battery cells pretty hard, you'll have pretty bad degradation when discharging to 0%. I think most EVs have a higher cut-off, and most people don't discharge EVs to near 0% anyway.