C++11/14 can't be used without upgrading your compilers. Go and Rust use standard toolchains.
Go is also crossplatform, whereas gcc/clang don't like working on Windows, and Microsoft doesn't like implementing the full C++11/14 specs without waiting years after the open source community has already been using the full specs. This results in fragmentation.
Comments
C++11/14 can't be used without upgrading your compilers. Go and Rust use standard toolchains.
Go is also crossplatform, whereas gcc/clang don't like working on Windows, and Microsoft doesn't like implementing the full C++11/14 specs without waiting years after the open source community has already been using the full specs. This results in fragmentation.