To me the biggest issue is the relative one way economic (let us set aside the intangibles, because one cant feed themselves on such) proposition of these devices (upfront cost of "paying" [more like renting since its default locked in to a provider] for the device, and the free "work" people provide with their queries). Reminds me of the proposition of the collect your dna as a service companies.
I guess the incentives of everyone running an instance of sphinx, and sharing models/feedback error corrections continuously with each other in the background with the ubiquity of torrenting now and decreasing reliance on the Amazons in the middle isn't here yet.