2^64 bytes is enough for any human

What an idiotic argument. Has he never heard of virtual memory? You might want to memory map things that aren't necessarily on a die inside your computer, in fact that's already a very common pattern, with mmap(2) and similar system calls.

And the idea can be extended to large computer clusters if not the entire planet, in which case you might be looking at 128 or 256 or a non-power-of-two figure, IPv6 addresses already taking up 128 bits. In which case it would probably also be a good idea to think about variable length pointers to decrease the overhead and address Donald Knuth's complaints in his "Flame About 64 bit Pointers" [1]

1. https://cs.stanford.edu/~knuth/news08.html

date, 2004