Say the crypto of your choice dips by 15 percent, but if you want to cash out you'll have to pay capital gains tax + the exchange fees. You then may decide to just leave the money in the market in hopes that it reverses the trend. Thus the market is not really working freely in my opinion.
Sounds like a libertarian paradise but these also comes with double edge since it leaves his citizens without consumer protections, makes value speculative to trading volume therefore subject to foreign control and limits the government enforcing power.
The market is free, exchanges aren't.
What stops you from exchanging your crytpocurrency to a fiat currency that doesn't impose taxes?
But yeah, this is probably the closest we have gotten to a libertarian test-drive through technology.