> Then, one day, ten or twenty years from now, we'll realise that "fiat" currencies have been blockchain based since some un-trumpeted central bank upgrade eighteen-months prior.

Tom, Dick, and Jane may not notice, but I would hope that those investing in that space, and those building out the technology, would :) The general public may not have an appreciation for the complexity behind it, but I assume many of Hacker News's readers, now and in the future, will be working on the forefront of developing this new technology.