“It’s an exciting development. I did not know that they were coming out with not one but two of these [quantum computing results] in the same week,” says Scott Aaronson, a theoretical computer scientist at the University of Texas at Austin. “That's pretty insane.”
Source: Scientific American China Is Pulling Ahead in Global Quantum Race, New Studies Suggest
Does "That's pretty insane" mean "That's pretty amazing"? Or does it mean "That's pretty foolish"? The former is informal while the latter is formal (normal sense of "insane"). I am not sure.