Every now and then, we feel like it is our duty to sound the alarm because the threat is very real.

LOL, when aren't you "sounding the alarm"? You are the boy who cried wolf times several orders of magnitude.
:-)

"The world that we know it is going to dissipate into a cold nothingness".
Does Elon Musk mean that at some point, technology is going gives birth to alien beings which can only rise if they destroy the world that creates them?

No, you knucklehead, he is talking about the inevitable heat death of the universe. How could you possibly conflate that with AI taking over the world?