The smartest thing in any of my vehicles is an aftermarket Android Auto unit so I can't speak from personal experience, but there are various things such cars can do where the connectivity could be useful. Three I can think of are notifications/video of things happening around the vehicle at the time of occurrence (a la Tesla Sentry mode), being able to remotely start the vehicle to give the air con a head start on a hot day, and over the air updates for bug fixes or possible new software features without having to go near a mechanic.

Part of the problem here is that the things that can invade privacy do have genuine use cases, it's just that you can coopt them to also gain information. For example even the seemingly hard to justify internal cameras could have a genuine safety use by watching the driver for fatigue symptoms. If effective this would save lives over a car model lifespan, so you're balancing obvious privacy issues against the idea that such inconvenience is worthwhile if it saves a life (a sentiment more typically seen in speed limit debates, but applicable here too).