BitCoin seems to be designed as a weapon aimed at destroying central banks and money-issuing banks, with Libertarian political agenda in mind-to undermine the country's ability to collect taxes and monitor the financial transactions of its citizens.
IMO,i think it is not typically the reason why bitcoin has made.Bitcoins purpose is not to destroy banks,maybe blockchain technology and etc. is the reason why the banks are being threatened and afraid of losing their revenues
Bitcoin is not a threat to the economy,infact it helps the economy into their financial matter.
Bitcoin was made primarily to eliminate the need for a peer-to-peer transaction between individuals. In other words, convenience revolves around the reason for its existence in the world today. Its technology surpasses any electronic payment currently as the blockchain technology introduced a revolutionary way for transactions between people. Economically speaking, bitcoin has supported individuals into earning alternative income due to various services being offered.
For example, under the marketplace many people seek for specific services/products and they use bitcoin as the payment for such. Instead of having to do labour which requires strenuous effort, cryptocurrencies in general eliminates the need for that. The money earned by individuals through cryptocurrencies circulates around the economy which makes the market liquid.
It's not threat to the economy but only on banks. Their users are going to be divided and instead of people letting their funds getting taken care of by bankers, they are going to keep it themselves and provide their own security because of cryptocurrencies.
Banks do consider bitcoin as a threat into the investment perspective and not more than that. Banks are also considered as business, wherein they earn income through various loans (provided by bills, notes, etc.) and they utilize their income in order to control the money supply in the society. Having bitcoin in the picture, people would rather invest their money into this aspect than into banks- which makes it a threat to their business.