Same here; I used to be a huge fan of D but then C++11 came along and solved most of my problems (and some that I didn't know D had).
Also compiling C++ code in C++11 mode won't make many developers use Modern C++, instead of C compiled with a C++ compiler, as many still do.
Maybe it works for your context, but in a global context we need to have safer languages for systems programming. Which were already available when C didn't had any meaning outside UNIX.
And if your company won't let you upgrade compilers, then it certainly won't let you switch languages altogether.
With a Pascal like type safety. You need to be explicitly mark your code as @system to be allowed to do C like tricks.
This alone is a very big advantage.