Reference counting is neither lower latency nor lower memory overhead than basically everything else.
Reference counting requires atomics on every single object. Per object atomics are quite unfriendly to modern microprocessors.
There is either very little contention with lots of atomics that you don't need or you have high contention with atomics that are blowing out your cache lines repeatedly.
In addition, managing reference counts practically requires RAII semantics and all of the baggage that goes along with that. Doing reference counting in C, for example, is extremely error prone.
Reference counting requires atomics on every single object. Per object atomics are quite unfriendly to modern microprocessors.
There is either very little contention with lots of atomics that you don't need or you have high contention with atomics that are blowing out your cache lines repeatedly.
In addition, managing reference counts practically requires RAII semantics and all of the baggage that goes along with that. Doing reference counting in C, for example, is extremely error prone.