Why manipulation is not true? like just imagine if you are a owner of a project and your team is holding 30% coins in total supply, if your team is start selling all of those coins, that will not be highly reflected in the coin price? ..
This is exactly what happens when a team starts selling its tokens, they are joined by other holders who make panic sales, which leads to an even greater price reduction. And when the price reaches the minimum values, the team buys tokens at a reduced price and thereby increases their number in their wallet.