In my opinion, if the income from crypto is large enough and stable per month, the government may impose taxes on our crypto income, meaning that the tax is based on fiat currency resulting from the withdrawal of exchangers.
I don't think there should be any taxes to crypto profits.
However, most goods you buy in the store already has taxes in the price, so if we'll be able to buy with crypto that means we pay taxes already
But we can't actually use it, not in all of the countries we can use bitcoin to buy goods. Usually we convert out bitcoins and even other crypto currencies into fiat and in terms of our local exchanges, even though I am using their servcies, I can't actually see any taxes deducted from the converted amount.