Let me correct you here: it's not the speed of light the issue here it's the parasitic capacitance that grows with the size of the subarray. From that point of

Let me correct you here: it's not the speed of light the issue here it's the parasitic capacitance that grows with the size of the subarray. From that point of view, when the array is large enough, the particular technology you adopt has only minor influence on the access time.