Yes, phones do have microphones too. The were a confidentiality risk even before becoming mobile. You also have piping running through your house, which could be tapped, you don't even need microphones, and the EM field emitted by your monitor can be read across the street. So why even care? Why should I encrypt anything, if I can't even prove not living in an all powerful simulation?

Back on topic, it's not a phones intended purpose to snitch on you, they usually do not listen into the room, without extremely malicious manipulation, and more so you simply can not realistically avoid having a phone in your reach, today. If I were talking business I would probably leave the phone outside too, for that matter, and I don't trust cheap communication hardware, either.

In real life drawing analogies by principle doesn't make for a good argument, most of the time, as life is adaptation and compromise, not a path through a logical circuit.

Do you honestly not see an obvious difference between a phone and an Amazon wired device intended to record and remotely analyze what's happening in the room?