1. It would require to control hardware development, manufacture, and operation.
2. It would require to control Software development and operation.
3. It has no purpose other than the one given to it by its creators/operators.
Right now, every so-called "AI" is completely dependending on hardware and software being "fed to it" by humans.
There's no "AI" creating software, there's no "AI" creating hardware, let alone operate it, and there's no "AI" operating or controlling other "AIs", nor is there any "AI" that acts in any way or form selfish.
It's certainly fun to think about how a self-motivated language model that tries to take control over the humans that operate its server farm, but without an army of (humanoid) robots, it certainly poses no danger, as it cannot replace humans or even threaten them.
The big challenge with "AI" is that we will probably be unable to distinguish its output from the one of a human being. This will have severe impact on how we can trust any form of remote communication.