What are the worst parts of D?

[Dicebot via Digitalmars-d]

On Saturday, 20 September 2014 at 12:39:23 UTC, Tofu Ninja wrote:
> There was a recent video[1] by Jonathan Blow about what he 
> would want in a programming language designed specifically for 
> game development. Go, Rust, and D were mentioned and his reason 
> for not wanting to use D is is that it is "too much like C++" 
> although he does not really go into it much and it was a very 
> small part of the video it still brings up some questions.
>
> What I am curious is what are the worst parts of D? What sort 
> of things would be done differently if we could start over or 
> if we were designing a D3? I am not asking to try and bash D 
> but because it is helpful to know what's bad as well as good.
>
> I will start off...
> GC by default is a big sore point that everyone brings up
> "is" expressions are pretty wonky
> Libraries could definitely be split up better
>
> What do you think are the worst parts of D?
>
> [1] https://www.youtube.com/watch?v=TH9VCN6UkyQ

There are so many it is hard to chose worst offenders.