Yes because security researchers and hobbyists would never compare an isolated device to one plugged in next to a TV or in a crowded room, there just isn't any data to support that anything like that is happening. As many other commenters have said, these devices are less complex than a cell phone and most people have no issues carrying one of those around. If one of your devices was "tapped" it would be that one.

Most text transcript services are too complex to run on the tiny little processor in these devices. They would be sending audio or nothing at all