You don't have to research sentient AI, but that means you'll be missing out on the bonuses they give. Other civs might research AI even if you don't, so your luddite civ will fall behind, and if their robots revolt it might spill into your empire enyway.Preimse of robots stabbing you in the back is pretty retarded. Giving them any kind of programming that sort of gives them "free will" also so.
"Sire the robots are rebelling!"
"Rebelling? Why?"
"We programmed to become unruly if they didn't get oil change often enough"
...
Sounds like choices have consequences
Yeah and that would go really cool with espionage (once they include it in an expansion) and CBs. An alien empire conducting technology you deemed too dangerous (should be a button where you can list technologies as too dangeroes) should give ou and automatic Casus Belli on that empire so you can stop them from doing it. But first you need to know what technology are they working on now (espionage would work really well with this).
And things is they even have something like that in the game already, but only for Fallen Empires. When you have a Knowledge Keeper trait on a Fallen Empire it will attack anyone who develops technologies that they are scared of or think younger races shouldn't have. But I don't really like mechanics that are exclusive for the AI. Everyone should play by the same rules.