that applies specifically to this artificial problem google created to be hard for classical computers and in fact in the end it turned out it was not so much.

that applies specifically to this artificial problem google created to be hard for classical computers and in fact in the end it turned out it was not so much. IBM came up with a method to do what google said it would take 10.000 years on a classical computers in just 2 days. I would not be surprised if a similar reduction happened also to their second attempt if anyone was motivated enough to look at it. In general we have thousands of optimisations problems that are hard to solve but immediate to verify.