Glad to hear it's helpful, thx.
I know amazon's got a different motivation matrix than a startup; e.g., Amazon won't die if some feature isn't delivered by the next trade show, but they do have competition from the other majors.
That said, amazon certainly also has the funds available to invest in a parallel risk team. If they're not motivated to do it from the risk to their users, the best argument might be the potential reputation setbacks if stuff like this gets out there & causes problems, bad press, reputation for creepiness, etc.
I know it always seems inevitable that you'll weather the reputation hits from errors and just press on to greater usage/adoption/sales, but it will always seem that way from the inside -- until it doesn't. Google's experience with Glass comes to mind; could have been a fantastic product, but it went just under the tipping point of being creepy, and poof, they're gone. It'll be a generation before anything similar comes back.
I'd hate to see that happen to Echo/Alexa. TBH, it looks like this product has both greater potential, and also greater creepiness potential than Glass ever did.