Private security footage is nothing new to criminal investigations, but two factors are rapidly changing the landscape: huge growth in the number of devices with cameras, and the fact that footage usually lands in a cloud server, rather than on a tape.
When a third party maintains the footage on the cloud, it gives police the ability to seek the images directly from the storage company, rather than from the resident or business owner who controls the recording device. In 2022, the Ring security company, owned by Amazon, admitted that it had provided audio and video from customer doorbells to police without user consent at least 11 times. The company cited “exigent circumstances.”
Should there be an expectation of privacy in public? Definitely wrong for footage to be able to wirelessly, without the owners consent, leave a car.
No, but there should be an expectation of not being recorded by every car you come across.
Again, the expectation in public is that you don't have privacy.
The expectation I would have is that your own car isn't going to collect evidence that could be used against you. And that it won't collect data in your own garage or on your property.