Today the Movement coin has experienced a sharp drop in its price - has there been any bad news? Or it's just some whale or dolphin dumping his coins?
Let them dump

they are missing out a great opportunity of the future.
Shortsighted people usually dont survive on this market and they are always to first one to dump at first sight of blood.
quite normal. Some people see small gains and immediately sell for those. But they actually will never achieve a 10x ROI or something in Crypto.
Besides this impatience, most do not follow the project and just sell the airdopped token. But if they knew how good the project is coming along these days, I doubt they would sell
That's true, so many people get in crypto just to grab the daily bread, as soon as possible, with close to no clue about what they are getting and selling and with zero long term vision.