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.
If you do not see and do not know who is behind this, it does not mean that it is decentralized.
The current fall in the market looks man-made, and this is the best way to confirm my words.