old way: (hoarding coin for 5 years=no fiat gains for 4 years 11month 27days)
Additionally, at the time of paying the taxes with BTC (or any other crypto), the person making the payment will experience capital gains (or loss) on the value of the coin that they used for payment even though they didn't convert it to fiat. Therefore, they'll owe capital gains tax (or potentially can deduct a capital loss) when they file the next year's taxes. According to the government's current rules regarding cryptocurrencies in the U.S., spending cryptocurrencies to make a payment on anything is identical (in terms of legal tax responsibilities) to converting it to the same amount of fiat and then spending the fiat, and the same taxes are owed even though you didn't personally covert to fiat.