And their conclusion was completely wrong.
Because unless you’re a journalist, a lawyer, or have some kind of role with sensitive information, the access of your data is only really going to advertisers. If you’re like everyone else, living a really normal life, and talking to your friends about flying to Japan, then it’s really not that different to advertisers looking at your browsing history.
These days, a private conversation about pregnancy, abortion, voting, or your feelings about geopolitical stuff like Gaza or Ukraine could absolutely be used against you, depending on where you live.
Wireshark may or may not help you here. The proposed mechanism is abusing the wake words, which are processed locally on the device. Each marketing wake word could be processed, set a flag and go back to sleep with no network activity. Periodically a bit array of flags would be sent to the server with any other regular traffic (checking for notifications, perhaps). The actual audio never gets sent. I'm not saying that Facebook actually does this, but it's a reasonable explanation for the behaviour seen in the Vice article.