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.