The statements ascribed to Rapoport are nonsense --- they must have been garbled in the transmission. I'd guess he may have said that the approaches to nonabelian class field theory before Langlands were a dead end.

The google translate of the original paragraph still makes no sense. Perhaps one could make sense of it in context. The main theorems of abelian class field theory were proved in the 1910s but there were major improvements to the theory in following years (Hasse, Chevalley, Artin, Tate ...). Abelian class field theory remains of fundamental importance.

"don't waste your time with class field theory" by itself doesn't make sense either. The Langlands program incorporates a nonabelian class field theory, and to understand the Langlands program you need to understand abelian class field theory.