Wrong, profit or income will only it is if it is counted in fiat. You can start from 1 btc, and trade, gamble, hold, or anything, then you get 10 btc in return (2 years later, for example). However, what do you really get if you buy 1 btc at 10000 USD per BTC, and two years later, you sell 10 BTC for only 10000 USD in total. It means BTC drops 10 times after two years in the example.
That is, if one considers its capital to Fiat money not in bitcoin. I know several crypto anarchists who consider their capital exclusively in bitcoins and they do not care how much it is in dollars.