Yes, right, maybe this is the reason why many parties refuse crypto. It would be dangerous for a country if the country makes crypto as a currency, if crypto is very easy to manipulate, then a country that embraces crypto will be easily controlled by the evil mafia mafia.
You cannot stop people with large amounts of money to manipulate the price of commodities on markets. We are talking about very skilled traders and people who are operating in absolute secrecy within Cartels. Wall Street has implemented sophisticated software to detect and reduce manipulation on the stock exchange, but it is still being done.
The Bitcoin exchanges does not have this software and with Bitcoin being traded globally on unregulated exchanges too, you will find that manipulation of the market is rampant.
This is one of the reasons why the SEC does not want to approve these Bitcoin ETFs, because the price of a bitcoin is being manipulated and people need to be protected from these greedy bastards.