[jlouis]

If you squint your eyes enough, automatic reference counting is a garbage collection method. But if you are going down that road, there are other garbage collector schemes which often produces way better performance in the common situations, i.e., copying collection or Mark'n'sweep.

But it is a trade-off. Refcounting collectors need to address pointer cycles. And they are also quite slow due to all the refcount bookkeeping going on all the time. But they have the nice property that the lifetime of an object won't linger around in a zombie state. And there are no point in time where the system is in a "collecting" state and cannot give service.

That said, many modern, multi-core malloc() routines contain a lot of ideas from GCs in them. The gap is closing fast.