Altcoins follow the trend for bitcoin, many of them are worthless and will only gain some value only when the market is in an excessive bull. Many of the top coins are not deriving value from use cases, only from occasional pumps and dumps
Based on what you say this? indeed, as seen by many Altcoins who follow the trends of bitcoin, but there are also Altcoins that have increased prices without depending on the trend of bitcoin, this depends on the number of interested buyers who are increasing on an Altcoin, thus the volume on the market will also increase along with the price of the unit too.