There are almost 3,000 altcoins or cryptos that are not bitcoin. But most of these are tied to bitcoin w.r.t to their price values. The typical reason is that their value is measured in bitcoin.
Mostly before investing in altcoins, people buy bitcoin and then exchange it for altcoins.
Looks like their only means of trading is through bitcoin and there is no other way. In this case, There price will only grow when bitcoins are in a good position in the crypto market and it means, the price is not dramatically decreasing. Because the price is not stable, you will find them one after another losing their values like others that already turned to shitcoins. Therefore, bitcoins cannot become like them because it always needs new coins.