That's concerning. To be clear, I once worked on a company that developed an audio-based ACR technology to be used in conjunction with a secondary device that users would turn on at their will. Anything more invasive would have been substantially challenging in legal aspects so that was the status quo more than 10 years ago. So it's new to me that not only ACR is somehow pervasive in "smart" devices but also they even don't care whether they are really being used as a television (which has no other interaction mechanism in principle, and ACR is not only for ads).