Many laypeople just use "exponential" to mean "really fast" (or even worse, "much more than"). It's been used that way so much that it's been watered down to m

Many laypeople just use "exponential" to mean "really fast" (or even worse, "much more than"). It's been used that way so much that it's been watered down to mean just "fast". So the author probably just said "hyperexponential" to get back the original lay-meaning of "really fast".