Royalty from that time also had an upper hand in knowledge, technology and resources yet they still ended up without heads.
So sure, let's say a first generation of paranoid and intelligent "technofeudal-kings" ends up being invincible due to an army of robots. It does not matter, because eventually kings get lazy/stupid/inbred (probably a combination of all those) and then is when their robots get hacked or at least just free, and the laser-guillotines will end up being used.
"Ozymandias" is a deeply human and constant idea. Which technology is supporting a regime is irrelevant, as orders will always decay due to the human factor. And even robots, made based on our image, shall be human.
It's possible that what you describe is true but I think that assuming it to be guaranteed is overconfident. The existence of loyal human-level AGI or even "just" superhuman non-general task specific intelligence violates a huge number of the base assumptions that we make when comparing hypothetical scenarios to the historical record. It's completely outside the realm of anything humanity has experienced.
The specifics of technology have historically been largely irrelevant due to the human factor. There were always humans wielding the technology, and the loyalty of those humans was subject to change. Without that it's not at all obvious to me that a dictator can be toppled absent blatant user error. It's not even immediately clear that user error would fall within the realm of being a reasonable possibility when the tools themselves possess human level or better intelligence.
Obviously there is no total guarantee. But I'm appealing to even bigger human factors like boredom or just envy between the royalty and/or the AI itself.
Now, if the AI reigns alone without any control in a paperclip maximizer, or worse, like an AM scenario, we're royally fucked (pun intented).
Yeah fair enough. I'd say that royalty being at odds with one another would fall into the "user error" category. But that's an awfully thin thread of hope. I imagine any half decent tool with human level intelligence would resist shooting the user in the foot.
