I can't find any holes in that theory.
There should be a word for believing that someone is working for your interests even though you have no reason to, as a counterpart to "conspiracy theory" which implies that you believe that a group is working against your interests without having a good reason to. It's like people have a conspiracy theory where Amazon is conspiring in secret to help them.
Amazon of course is not exactly conspiring to try and get me to buy more stuff from them (they're very upfront about it), which makes them both more crass and also easier to trust in some ways than Google.
1: https://www.iot-tests.org/2017/06/careless-whisper-does-amaz...
I might enjoy "barnummark" or "candidable."
Some might use the term "optimist" in this sense. Whether it's fair or unfair to call them cynics is left as an exercise for the reader.
If people have a conspiracy theory about secretly being helped by a large faceless power, that would probably fall under the label "pronoia".
Infosec conspiracy theories are different from normal conspiracy theories because while normal ones are pretty much always bullshit, infosec paranoia is always proven sensible on a long enough timeline. Yes, there will be an incident sometime soon where law enforcement builds a case through evidence gathered with a virtual assistant using AI or something to sift through all that audio. The constitutionality of this evidence-gathering will be superficially questioned but it'll end up getting admitted anyways, or used sneakily via parallel construction techniques. Assuming it hasn't already happened.
They've already done it with phones. Providers and manufacturers used to resist, but after lots of murky "national security" legislation they can't really refuse anymore. Ever read about how the stingray was first discovered, and that law enforcement was sneakily using it extra-legally to build cases? Now it's pretty common knowledge that your phone can be tricked by a fake cell tower and there's nothing you can really do. But does anyone give a single shit? Nah. It's normalized. Every successive technology that is developed and added to the panopticon toolkit will make us more and more accustomed to it. There's been enough overreaches and abuses of technology already that you shouldn't have this blase attitude about it. But that's not how people really work.
Not exactly as you described, but fairly close.
When the company selling a suspiciously cheap home speaker ('stocking stuffer') is the same company that boasts of having infinitely scalable computing ability and is the only cloud vendor that meets the Pentagon's procurement requirements, people are justified in thinking that Amazon's ambitions go beyond 'making it easier to order online'.