I admit that I went a bit overboard with the complaints about users, as seen in the out of context quote ;) This was mostly to accentuate that the few folks doing anything about D were (and still are) being ignored or actively bashed by the people in charge.
Regardless of any technical issues, that cultural issue would be enough to put me off. Sometimes it is the case that the language's maker's interests diverge from that of its users (e.g. OCaml is developed by language researchers without direct commercial interests) but it's rare to see them poisoning their own ecosystem.
It's an interesting comparison, since Haskell is about 20 years old and D is about 10. I remember using Haskell about 10 years ago, and it was a rocky experience.
Back then Haskell was mired in "avoid success at all costs" - AFAIK D isn't a research language, it was always targeted towards production use.
Can you blame them? Everyone has real work that they need to do. Languages like Haskell and OCaml may be lacking in bread-and-butter libraries, but their toolchains are pretty solid, GHC is a fantastic compiler. The language landscape is brutally competitive; for any language to survive the pain of learning it has to be rewarded with a big boost in productivity (or salary...).