Re: What the article leaves out
That's only true for "anonymized data". If the data is truly anonymous, i.e. nothing in it to tie to a particular device, person or other recording then the only way you can de-anonymize it would be based on the content of the recording. How many interactions with Siri, Alexa, Google, Cortana do you think include anything like that?
The problem you speak of is when they for instance remove the name and address from personal information, but leave the sex, age and city. Combined with other information something like a "30 year female living in <town with population of 20,000>" would already be narrowed down to perhaps a hundred or so, so it wouldn't take much additional like "single mother of two and Alexa user" coming from another source to narrow it down a single individual.