That's true, but you can write C code in D as well, so switching to D won't make people write idiomatic code either. If they won't learn how to use one correctly then they won't care enough to use another correctly.
And if your company won't let you upgrade compilers, then it certainly won't let you switch languages altogether.
And if your company won't let you upgrade compilers, then it certainly won't let you switch languages altogether.