I shudder to think what one man with a texta could do here. It isn't that hard to turn the acyclic graph into a cyclic one.

This is quite a bad argument, somewhat akin to "small drones can't kill anyone because there are no weapons on them!" back 20 years ago. Well, ok. So what if someone adds the thing that is missing? And there is no reason to think that a stochastic parrot can't go rogue, the evidence is a stochastic parrot can engage in any intellectual activity we care to define and benchmark.