>This can't be universally true. If food gets continually cheaper, unless the cost of owning land and farming it goes down by the same amount, farmers must eventually make less money than before (or be driven out of business entirely).

Or the same farmer could be producing more food than before, but at a reduced cost. He would make the same amount but the price of food would be lower.

>And I don't quite buy the comparison between technological progress (where things get cheaper due to massive amounts of competition and research) and switching to a fiat currency which is arbitrarily limited (bitcoin). Using bitcoin doesn't guarantee technological progress.

No but technological and economic progress is almost guaranteed anyways. A currency like bitcoin means you actually get the reward from it in the form of cheaper prices over time.

>Yes, printing money is in effect a government tax for usage of that currency.

Exactly. In that sense bitcoin and currencies like it are free of that form of taxation which is a good thing for everyone using them.