Hmm I don't understand this. I guess they are only taxing crypto that is being changed back into the won or fiat currencies right?
I mean how do you tax bitcoin or any altcoin? So if you never convert your coins into any fiat currencies you would still never need to pay tax.
Bitcoin isn't their national currency of course they can't tax it unless its being cashout to WON and that's when they can get their cut. It all comes down still to how much is the value of a btc, if it goes so high, then the money they can collect is much higher. The high the BTC price the bigger the money the btc traders can provide to their economy.