> There are multiple places around the world that accept bitcoin to pay for their taxes.
No there are not. There are jurisdictions which sign agreements with Bitcoin exchanges to integrate them into the tax payment process. The exchanges
must always be able to source enough local currency to meet the payment. The government does not accept and hold Bitcoin - the value of your taxable obligations, once determined, can change in Bitcoin with the exchange rate - whereas my tax obligations in local currency don't, provided I hold local currency.
> Is gold worth nothing, because eventually people have to cash out? Gold is also deflationary.
Gold is not used as a currency today. Neither is Bitcoin. The argument over deflationary currency presumes a world in which Bitcoin fulfills the stated objective of it's adherents as a currency.
Bitcoin and gold are both commodities today. As a commodity Bitcoin has very little to recommend it. Strictly speaking this is true of gold as well, but gold is historically very complicated, and has the benefit of being a physical resource which displays some physical scarcity (of note: gold as a currency isn't strictly deflationary, your inflation rate it just pegged to the rate of mining and discovery).
On gold as a currency - Middle Ages economies routinely bankrupted themselves by making huge windfalls in gold, and failing to recognize that all they'd done was drive a lot of inflation (i.e. the Spanish after they found the Americas - they didn't raise taxes, so the royal treasury found itself in debt even though by simple thinking they should've been very wealthy). Bitcoin has all these problems, but unlike gold also consumes resources to retain it's value. A block of gold after 10 years is still just a block of gold.
> I am in favor of free choice.
And I'm not arguing anything should be illegal. I am arguing rational people should recognize what Bitcoin is, and think carefully about how they value it. It is not what it's advocates say, and it is mostly powered by the reality that your average person does not think carefully about the nature of money very often.