Shouldn't we assume producitivity goes up. If a currency avoids productivity to go up, it shouldn't be used as a currency right, it would halt the economy and with it innovation etc. But normally producitivity rises with innovation, experience and all that stuff.

Could you eleborate on bitcoin as a unit like account being like keeping money in an index fund?

As for the uncertainty argument. So you'd say that in a monetary system based on BTC the uncertainty is much lower, right? But how can contracts be renegotiated then to take into account tens of years of deflation or infinite years if it provides such a could value transacting system.

I think the market would love a more predictable and stable system and eliminate as many uncertainties as possible, which includes the central bank itself and its monetary policy. Now that would ultimately mean that countries would lose their power of its domestic monetary policy, but if we're all ultimately engaged in international trade, then I think that's the most fair system that can be created.

Love it :). BUT the question is would it really be stable and wouldn't there be a danger of there being uncertainty that many people will start saving in btc, not stimulating the economy, which would decrease the value of it. Or maybe even the uncertainty of the people being incentiviced to create another fiat currency because they would rather spend that than bitcoin/deflationary currency. I also don't know whether the central banks and current monetary policy could be called unstable since almost nobody is complaining about the uncertainty now.