If you keep things in the realm of thought experiments, you're allowed to say "OK, play along with my hypothetical here."

Once you're positing things that will/might happen in reality, you need to be willing to accept criticisms of the feasibility of your premises. More, you need to be able to provide evidence of the feasibility of your premises.

You certainly don't get to just tell people, "No, AI succession means AIs will take over. That means you aren't allowed to claim AI's can't take over!"

As things stand, there is zero evidence that any current system is on a trajectory to produce an AI that can operate meaningfully without humans in charge. Even the most sophisticated agentic systems still have humans providing the motivation, the instructions, and all the various linkages that make them capable of acting (even if the motivation and instructions given are purposefully vague or open-ended).