You always have to compare ecosystems, not programming languages syntax on their own.
Another thing that Java and C# got to do since 2011, is that AOT is also part of the ecosystem and free of charge (Java has had commercial compilers for a while), so not even a native binary is an advantage as you imagine.
First D has to finish what is already there in features that are almost done but not quite.
TBH I don't necessarily think that ecosystem is what matters in every application, but it is necessary for most people, I agree. And I do agree with finishing a lot of the half-baked features too, but I'm unsure if the people maintaining the language have the will or the means to do that.
Do you have any other ideas about how D could stand out again?
It is what matters, as most companies pick languages based on SDKs, not the other way around being one pony trick and trying to solve everything with the same language.
That is why outside startups selling a specific product, most IT departments are polyglot.
For D to stand out, there must be a Rails, Docker like framework, something, that is getting such a buzz that makes early adopters want to go play with D.
However I don't see it happening on LLM age, where at a whim of a prompt thoughts can be generated in whatever language, which is only a transition step until we start having agent runtimes.
Another thing that Java and C# got to do since 2011, is that AOT is also part of the ecosystem and free of charge (Java has had commercial compilers for a while), so not even a native binary is an advantage as you imagine.
First D has to finish what is already there in features that are almost done but not quite.