I think you're right, I was only thinking about raw audio being uploaded to the cloud. In the future, there might be more and more local machine learning happen

I think you're right, I was only thinking about raw audio being uploaded to the cloud. In the future, there might be more and more local machine learning happening on the devices and the extracted metadata being uploaded unnoticed. On the other hand, I still think people can analyze the hardware and software running on the devices. If there are "black boxes" doing something unknown, we should be worried, particularly if they are always powered on and have the processing capability to analyze audio content. Still, the original claim in the article was that there is a lot of this metadata being uploaded right now. I don't think anybody has verified that claim, even if it could be true.