Bitcoin is not an outright threat to fiat. Fiat remains fiat and can never be replaced by bitcoin. Because in truth bitcoin is only a revolutionary digital currency which is another option for today's more modern payment problems. Governments have their respective regulations and every government in the world has different regulations regarding the application of bitcoin in their country. Some of the people who scare about bitcoin are those who are against bitcoin and really intend to drop bitcoin. Bitcoin which is identified with criminals is certainly not entirely true, because traces that are generated from using bitcoin cannot be erased, making it easy to catch criminals by tracing bitcoin transactions that have been made.