But would you use it to show ads if you have access to such a backdoor?
That's an easy way for your backdoor to be found out. Something like this, if it exists, would be too valuable to be used en masse.
Well if I am a secret service I could either try to force google to do it and risk a leak or I could find a way that there is something in it for them that has the benefit of providing plausible deniability?
same here, sometimes my understanding of a message doesn't make sense, but when gpt4 gives me the same understanding, it feels like we can't both reach the same conclusion by mistake. of course, that's not true, but in most cases, it's good enough.