There is no "must use GC" mode, as far as I'm aware, but the footguns you describe only exist if the programmers opt-out of the GC. It's somewhat similar to using JNI/FFM in Java: it's possible to escape the safety of the VM. Though it's much easier to do so in D.
I don't think D has a "must use GC" mode, so probably easy to hit a footgun. It's the footguns that make things hard (IMO).
There is no "must use GC" mode, as far as I'm aware, but the footguns you describe only exist if the programmers opt-out of the GC. It's somewhat similar to using JNI/FFM in Java: it's possible to escape the safety of the VM. Though it's much easier to do so in D.