@janriemer
Yes, but I am talking about the phone in your pocket and behavior-mining. Indeed, smartphones send constant streams of metadata to surveillance capitalists already, and that is so powerful that it made people think that surely the phone listens to their conversation. So that happens already. It is relatively easy to figure out where you are, and with whom you are there.
If your phone would send full audio or even video to a backend server, that would be a significant data flow and detectable.
Now these smartphone apps can grab and integrate an open source lib for text-to-speech and also add your full conversation to that stream. Natural organic conversation that is very attractive feed for LLM datasets and training, for instance. As compressed plain text it hardly increase the bandwidth required to stream it back.
Btw, I think for modern cars there are suspicions that they are listening in on conversations, but I am not sure the extent to which it is proven.