Does this also apply to non-Teslas? I'm guessing there's a bit of two-way communication from car to charger, for authentication/billing purposes but also for congestion fees like charging beyond 80%. Does the app notify you to take your car off the charger?

I understand the reasoning but sympathize with the luddites who shun all this technology. Imagine going on a road trip with your EV, stopping for a bite to eat and refresh while putting your car on the charger. Maybe there was a long line or you needed a long bathroom stop, so your car sits at the charger "too long" and you get a nice penalty.