128-bit addressing would add memory and processing overhead that would make it not worth it. 64-bit addressing is already more memory than will ever be in a Nintendo console (16 exabytes, or 16 million TBi).

The Nintendo Swirch 2 also has a 128-bit memory bus, which means it can move up to 128 bits of memory at once. This does make memory operations faster, effective increasing the bandwidth of memory operations.

The PS5 has a memory bus width of 256 bits. The Xbox Series S has 128 bits, and the Series X has 320 bit memory bus width. So, wide buses aren’t uncommon on modern architectures.