I can't argue with that: if I had to choose between the two, I'd rather be stabbed by the non-dominant hand. Obviously not being stabbed at all is a much better choice (when available).
I guess. For the kinds of clients who would want this device, this would just be like making it so that you're only a little bit pregnant. You either prevent the eavesdropping or you don't. The only safe tactic is not bring the device anywhere you don't want to be tracked or recorded. Or to technologically prevent it from operating somehow in a way that doesn't rely on verification -- such as taking the battery out, if you can, or putting it in a verified faraday cage that you keep in a soundproof box if you can't. And if you're the kind of person with a life so interesting they need to worry about about phone implants, maybe take battery removability into consideration when you buy the device.
It pushes the capacity for your adversary to operate into (slightly) slimmer confines, which is a marginal improvement.
Otherwise, your adversary can behave in an unrestrained manner. No?