> What part of the paper gives you the impression they imply voice assistants are listening to everything?

For me, it's this: "Your Echos are Heard"

So, the opening salvo. That's what gives me the impression they imply voice assistances are listening to everything.

I don't refer to voice commands or normal interaction as "echos" so the user of the word "echos" here implies something nefarious. Sure, it's the name of the product, but for me, it reads like something more.