The dash can serve multiple grammatical purposes... not just the one you picked to suit your narrative.
As I said, you are claiming to know the intention of the writer, which you have no way of knowing.
I see it one way, and you another.
"some economists" say we're doing well, and "some economists" say not so well... subject to opinion.
The powers not delegated to the United States by the Constitution, nor prohibited by it to the States, are reserved to the States respectively, or to the people