> A possible subtext to what you have written is that your employer (google) was mandating that you keep using the device at home as part of your employment... but that is outrageous and I would like clarification as I feel it cannot be true.

The requirement to use a Google device at home has never been imposed to the best of my knowledge, at least unless this individual was working on the product. Even then they would not be required to have it on unless they were actively working on it. If they were working on it, then they should know its capabilities and trust or distrust would be irrelevant, since they would have actual knowledge instead.

Also, the devices are not recording all the time. Presumably this experiment added the ability to treat fire alarms as a hot word, in support of the feature in question. That doesn't mean that Google has access to recordings of every conversation.

Also, there is no way anyone would ever be permitted to run the type of conversation analysis that the GP proposes. Far more benign analyses are rejected all the time due to privacy concerns. It's unlikely that any single person could even run such an analysis due to various access controls (e.g. the inability to access logs as a person-user, system-enforced requirements to run only checked in, reviewed code over logs). Even if a person could run an analysis like this as a rogue, it would be extremely risky, because they would get terminated immediately if it were ever discovered.

Also! Identifying useful, novel product ideas is beyond even Google's ML capabilities.