I've never bought into the "NSA/CIA made Intel create this" line of reasoning because, as you say, there was a legitimate use for this technology (misguided as its implementation was). Of course, I have no doubt that the NSA/CIA may have added further backdoors, or are withholding vulnerabilities in ME.

However, one thing that I've always felt conflicted about is why this feature is present in _all_ CPUs. Usually if someone wants to use Intel's AMT then they have a giant support contract with specialty hardware, so it seems odd that the core CPU feature necessary is present on all CPUs despite no user actually using outside of enterprise.

Is it because the bring-up, other low-level stuff, and things like PASP (DRM) were implemented on top of ME, and so it was not considered viable to re-do that on chips that didn't have ME (though I was under the impression that very early ME was not used for anything else)? Or was it just a matter of "it's easier to just use what we have for every chip"?