Isn't that how most GCs work?
Why would you do anything else? To release memory to the OS? That's not really a priority in most runtime systems, and I think wanting to do that is a pretty niche requirement.
I guess it depends whether GCs are always scheduled in an allocation or can be triggered another way. Either way that should be easy to disable.
I read somewhere that D doesn't have write barriers, so I would assume they have a hard time implementing more advanced GC features like generational collection or concurrent marking. It's not suprising that the GCs in the JVM achieve much better pause time.
You can definitely write useful Java applications where nothing gets heap allocated, through using existing objects, and through using scalar-replacement-of-aggregates.