Facebook was recently called out for listening to users audio messages on Facebook Messenger. They aren't alone. Apple, Amazon, Google, and Microsoft all have admitted to having contractors analyze audio from their voice assitants (and MIcrosoft's Skype service).
There's a stark contrast to these use cases. When you're interacting with a voice assistant, there is an expectation that a computer is transcribing the audio. That's the whole point. When I send you a voice note in Facebook Messenger, there's no expectation that anyone other than you will listen.
Of course, all of these activities were covered in the terms of service and privacy policies...but that doesn't mean users were aware, comfortable, or accepting of other humans listening in. Anonymized data or not.
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