There is no reason whatsoever to assume that "smart devices" with microphones are not listening and analyzing everything they can hear 100% of the time.
There is no reason to assume that the mute button does anything other than turn on an LED.
There's a reason that a 70" LED monitor costs $4500 while a 70" smart TV costs $399. They are making up the difference in revenue via the sales of your data. What you watch, what you eat, how much you argue, how much you have sex. What your kids talk about. If they can hear everything, they know everything.
I will have more about the state of IoT security in weeks to come. Suffice to say, things have not improved.