Can we be absolutely certain that everything before “Ok, Google” or “Alexa” isn’t being recorded, by the companies or by back doors created by the security services? Seems too much like a telescreen for my liking. The problem is I would love one I could trust!
If you want a voice assistant you can trust, you have to build your own out of open hardware and software and run your own hosted service for it, but the thing being hacked would still be a possibility. In the end, the only way to be sure is not to have one in the first place.