[Tsarbomb]

Not agreeing or disagreeing for the most part, but in 2009 all of the prerequisite technology for cryptocurrency existed: general purpose computers for the average person, accessible internet, cryptographic algorithms and methods, and cheap storage.

For 256 bit computers, we need entirely new CPU architectures and updated ISAs for not just x86/AMD64, but for other archs increasing in popularity such as ARM and even RISC-V. Even then compilers, build tools, and dependant devices with their drivers need updates too. On top of all of this technical work, you have the political work of getting people to agree on new standards and methods.

[mhh__]

256 bits in the case of a worldwide mega-computer would be such a huge departure from current architectures and more importantly latency-numbers that we can barely even speculate about it.

It may be of note that hypothetically one can have a soft-ISA 128 bit virtual address (a particularly virtual virtual address) which is JITed down into a narrower physical address by the operating system. This is as far as I'm aware how IBM i works.

[arthur2e5]

For what is worth, 256 / log2(10) is around 77, while the observable universe is estimated to have anywhere from 10^78 to 10^82 atoms. An 256-bit address space, if fully utilized, would produce Asimov’s AC from The Last Question.

More realistically though, we would throw away at least half that length like how we are handing out /64 blocks to everyone on IPv6.