Not much different than a mech cable snapping or the derailleur not being adjusted correctly by a tiny set screw and the chain ending up in your spokes.
Shit has catastrophic failures... that's never going to stop being a problem.
Mech cable snapping vs forgetting to charge the battery? Yes, end user error with the battery, but I’ve had exactly 0 cables snap and I put my bikes through hell.
As long as you have access to a phillips screwdriver, you aren't stuck in the little ring - you can tighten the high limit screw to pick your one gear (at least from the higher ones).
I've never had a rear derailleur cable "snap"; they stretch, fray and may eventually break right at the pinch point but these are either slow delays with obvious warnings or easily fixed on the trail. Compared to a connectivity or battery issue? They don't have nearly as high of likelyhood.
I’ve seen cable breaks happen, though not frequently. I’ve also seen chains break a lot more frequently, I know of 5-6 instances where it happened last year alone locally. All of these were a result of complete lack of maintenance as you point out, though I suppose it would be possible for a newer component to not show signs of wear and still fail.
Not much different than a mech cable snapping or the derailleur not being adjusted correctly by a tiny set screw and the chain ending up in your spokes.
Shit has catastrophic failures... that's never going to stop being a problem.