One particularly interesting example of this Kyllo v United States[1], where the use of infrared cameras to find grow lights inside a home was ruled a search (and thus needed a warrant) because infrared cameras were not common so the general public did not in practice see infrared emissions as "available to the public". The opinion of the court, however, did point out that their decision would be defunct when infrared cameras became generally available and used by the public. At that point the public would no longer expect infrared emissions to be private. (Presumably this expectation might create a market for e.g. ir-blocking paint? If that's even possible?)
Installing microphones that regularly send data to unknown 3rd parties normalizes the expectation that spoken word in the home is no longer private. When perceptions change, so will warrant requirements.
> We're not living in a violent, single-party totalitarian regime.
If that's you're criteria for when to act, you are always going to be too late to do anything. Some of us prefer the idea of detecting problems early - hopefully before the become violent.