I don't think ARC would work in D. You'd need support for
controlling the reference count in certain situations. You'd need
type signatures for different reference types. You'd have to
remove the GC.malloc function, as it would actually be manually
memory managed with ARC, or otherwise return a fatter pointer,
which would make it pretty useless. I hold more hope for someone
improving the garbage collector implementation. This will happen
sooner when someone who needs it takes the time to write it.
The key issue with GC is the pause time leading to dropped
frames. Google has recently shown that you can use a garbage
collector pretty excessively without losing any frames at 60FPS,
by minimising the collection time so it fits within a frame.
https://www.youtube.com/watch?v=EBlTzQsUoOw#t=23m
If you wrote most of your game code with allocations you
controlled and only had some minor GC activity with a
sufficiently well written garbage collector, you wouldn't notice
the GC getting in your way.
Whichever automatic memory management scheme you choose, if you
are writing real time applications, you will ultimately have to
optimise by taking more control of memory at some point. There's
no automatic solution for this.
