We don't even have 64-bit computers today. Look at the specs of your hardware and you will realize it's actually running on significantly smaller address buses.

We don't even have 64-bit computers today. Look at the specs of your hardware and you will realize it's actually running on significantly smaller address buses. Evidence: smaller powers of two showing up in maximum support specs. What we have are 64-bit instruction sets, which could have been used in the 16-bit era if we had wanted to for some reason. The real difference between 64 and 32 bit architectures is that when they went to 64, they said "who cares if we waste a few bits in pointers, we'd rather never have another change in pointer sizes." It represents no longer trying to shave every bit off of memory representations of code and data.