Tax policy is considered fiscal policy, separate from monetary policy.
Those rates can always be adjusted, and are regularly. For instance, the top marginal tax rate in the US for much of the 1900s was over 90%. It's now, what, 37%? So much for inflation taking away your gains :)
However, progressive tax rates mean as much for the viability of an inflationary currency as they do for a deflationary currency like a hypothetical BTC. That is therefore outside the scope of this conversation.
Those rates can always be adjusted, and are regularly. For instance, the top marginal tax rate in the US for much of the 1900s was over 90%. It's now, what, 37%? So much for inflation taking away your gains :)
However, progressive tax rates mean as much for the viability of an inflationary currency as they do for a deflationary currency like a hypothetical BTC. That is therefore outside the scope of this conversation.