Tiny community, even more tinier than when Andrei Alexandrescu published the D book (he is now back to C++ at NVidia), lack of direction (it is always trying the next big thing that might atract users, leaving others behind not fully done), since 2010 other alternatives with big corp sponsoring came up, others like Java and C# gained the AOT and improved their low level programing capabilities.

Thus, it makes very little sense to adopt D versus other managed compiled languages.

The language and community are cool, sadly that is not enough.