As always it is, Bitcoin is a digital cryptocurrency which has its own online system in order to have transacrions.Some countries banned it because of the threat that their income will be lessen.The earnings from Btc is not taxable.People may use as a means of trading, investing and even purchases for some available stores who adapts the use of crypto.Also government is afraid that people will only use crypto than the fiat which may lead to losses in some businesses,banks, establishments which does not offer btc transactions.