I don’t know why people keep thinking that phones are listening in on every conversation just so they can advertise ‘Volvo’ at you.

• they don’t need to - we give them loads of data voluntarily based on location data, what we search for, things we buy, things we ‘like’ on social media…

• they’d be stung for huge fines of caught doing it.

• it’d take enormous storage and processing power to manage all that data.

• Just think about how many things you talk about every day that you’ve never then seen an advert for (confirmation bias)

• my Google Home can’t understand me when I’m actually talking directly at it asking it a question, so the idea it can seripticiously pick out words while listening through my pocket is implausible.

A few things are very clear: 1. a phone with a voice assistant enabled has to listen all the time and 2. in order to train the voice assistant the data sometimes needs to be sent to the cloud and listened to by humans.

What is less clear is does this data ever get used for advertising. As you stated there are a number of reasons that make this unlikely.

Simple solution: disable your voice assistant. I do this today and I do not feel like I am losing anything. That said, with the pace AI is improving I can forsee a day when I would feel like I have to enable my voice assistant or I am losing some key functionality of my expensive smart phone service.