The only thing that could prevent it is shutting down all computer research. That isn't going to happen.

Besides, technically, non-human intelligence already exists - Koko the gorilla, for example, able to question her own existence, the meaning of her life, what death means, and various issues of morality.

There is nothing special about human intelligence, and nothing special about meat. What can be done on meat can be done on a machine substrate.

The fantasy is believing - without evidence - that there is anything magically unique, or unreplicable, about human intelligence.