I don't see how this argument makes any sense. Imagine that you have a sentient super intelligent computer, but it's completely airgapped and cut off from the rest of the world. As long as it stays that way it's both safe and super intelligent, no?
https://en.wikipedia.org/wiki/Ex_Machina_(film)
This is why I'm extremely opposed to the idea of "AI girlfriend" apps - it creates a cultural concept that being attracted to a computer is normal, rather than what it is: something pathetic and humiliating which is exactly like buying an inflatable sex doll ... something only for the most embarrassing dregs of society ... men who are too creepy and pervy to ever attract a living, human woman.