Blockchain can not survive without bitcoin, because bitcoin is the most important part of blockchain and also some other coins. The fame and price of bitcoin greatly influence the presence of blockchain and other coins. For that in the absence of bitcoin, the blockchain and other coins will also be gone, because they all move on to the movement of bitcoin.
Maybe you're right but I don't agree with your point. I think it is Independence and it can survive without Bitcoin.
I think crypto currency is just a product of blockchain technology, so with or without bitcoin blockchain will still licking good but its good to have bitcoin because it motivates everyone to use blockchain technology because they will enjoy of earning profit from crypto currency.