If bitcoin will be dead then cryptos might be dead too because every crypto move depends on bitcoin price as you always on the market and all cryptocurrencies are being traded with bitcoin and it is the major need of cryptos.
Bitcoin is the king of the cryptocurrency, if bitcoin died then there is a higher chance that other cryptocurrency might died too. Bitcoin is the famous cryptos of all and it is now the common cryotos that a person has. Although cryptos are independent to each other, there are some cases that one may affects the other cryptos.