99% of the coins in the market are useless and worthless. Many coins are indeed overpriced. Because of their high prices, they can't be pumped at all. The inflow of funds in the market is not enough to pump thousands of coins collectively, leading to a pullback in BTC, and many alts have already slumped by 50%. Because they have no intrinsic value, the buyers also know that they are worthless, so they will run away quickly. This results in a strong stampede effect, where a small drop in Bitcoin causes a significant fall in the valueless altcoins. On the other hand, the few valuable coins are still holding up well.