As explained many times:
1) You can save in many ways, not only hoarding the medium of exchange: investing, lending, hoarding real goods, paying in advance...
2) demurrage is not the same thing as inflation, their effects are different:
A) Inlflation is an accounting inconvenience. If you think that is not important, just think that the prices must grow exponentially and the period for a given product to increase one unit in price will become shorter and shorter with time. Eventually it will become shorter than a second
B) Demurrage lowers real interest rates while inflation only rises nominal interest rates
Computer hardware gets cheaper though. How much storage can a gram of gold buy today as opposed to ten years ago?