It's much more anti-fragile to have corporations who sponsor projects (as do we) than one or two key official sponsors. And it suits D's breadth too, because there's no single company that uses D for everything that's possible to do with it. Makes sense for Google to sponsor Go. Who is supposed to sponsor a language with versatility that encompasses C,C++ and Python and runs on the gamut of platforms. A single sponsor using D on Linux might direct energy away from Windows and embedded...
Mozilla is not a normal corporation though. I donate, and I suspect many others do, as well. So maybe rust could be seen to have a lot of tiny sponsors rather than one big one?
https://dlang.org/blog/2017/05/31/project-highlight-excel-d/