Remember, this whole thing about crypto is largely decentralized, thus, there is no single authoritative body in control of the crypto market. Although there are few centralized platforms among crypto, the market is largely influenced by the efforts and influence of the users of crypto. How well sellers and buyers treat the coins on the market affect the performance of the market.
You can see that the crypto market at the moment is constantly fluctuating with a very large margin.
Bitcoin has been around for a long time but has not been recognized by the world for legal circulation. Therefore, manipulating the market is very easy for a small number of people but holding the majority of bitcoin in the world.