They're closed-source, closed-hardware devices with microphones that are publicly acknowledged to send recordings they make to remote servers for processing. Th

They're closed-source, closed-hardware devices with microphones that are publicly acknowledged to send recordings they make to remote servers for processing. There's no non-testimonial evidence that they aren't eavesdropping. I'm not even aware of any testimonial evidence that was collected under oath (penalty of perjury or similar)! They don't really need to eavesdrop for advertising. They'd certainly end up facing some substantial regulatory scrutiny if they did. They could be required to eavesdrop by a national security warrant (or similar) which wouldn't be subject to regulatory scrutiny in the same way advertising would be.