According to CNBC, federal prosecutors had launched a criminal probe into the cryptocurrencies earlier this year based on suspicions that their price was being manipulated. I think it might be the main reason behind the price of bitcoin dropping to around $4000, but I also wonder whether it could be that authorities are afraid that Bitcoin and other cryptocurrencies are taking over the financial system since they're now so popular.
Until now there have been a lot of governments and authorities who are frightening the use of Bitcoin / Crypto. Basically they are worried because the crypto price movement is so fast that it is very likely to cause economic chaos in a country. Besides that, there are a lot of financial transactions that are free to do and have anonymity, making it difficult for the authorities to take action. This is what we are still waiting for, when various sectors support Crypto use, it is very likely that crypto can develop very rapidly. We are waiting for all that and I am very optimistic that it can happen.