Counterevidence: some of them (perhaps all) have a hardware switch to mute the microphone, a requirement allegedly set by the CEO.

Parallel evidence: the Ring acquisition has aggressively integrated itself with police forces.

Partial evidence: some of the devices are known to retain data even after being reset to factory settings (I presume it's a bug).

It has to be listening all the time for its activation command and we have no idea what it's doing with the data that comes in and is determined not to be the activation command.