Because of who Stephen Hawking and Elon Musk are.
They are talking heads. Political mouth pieces.
Stephen Hawkings, if he has the disease they say he does, should have died decades ago. So, if it is still him, he is in the 0.000001% of probability that he is still alive. My theory is that he is just somebody they dress up in a wheel chair where the speach writers back stage have a puppet to talk through.
Elon Musk hasn't built anything useful. His businesses are not legit. They all run off of govern-cement funding. Elon knows which side his bread is buttered on, and he follows his queues in making the speeches when needed. And if you follow him, you will notice that he contradicts his previous statements often. Nothing Elon has done has been revolutionary. He has just done it bigger with the help of govern-cement funding.
So, why would they sound the alarm? Mostly its a show. Mostly its to plant fear. T.P.T.shouldn'tB. are already working on super A.I. If they could actually build Skynet ™ they would have already done so. What they probably have in the works is a false flag with computer hacking and then the next step after boogyman hackers have warn off, is to say its rogue AIs.
I enjoy your way of thinking. I also believe the world is not as it is presented to us. The Narrative that TPTB keep up is so fraudulent and easily torn apart. I'll go along with your argument.
Well to be fair that is not YOUR theory on Hawking. But yes it is a very probable theory.