I believe the comment you are responding is making a distinction between the public key cryptography used to authorize spending from a private wallet, and the act of including a cryptographic hash of the previous block in the current block creating a blockchain (which only requires a strong hash function, not asymmetric cryptography).

Blockchains as defined this way have existed long before there was a proof-of-work based consensus protocol to make Bitcoin a reality. In their more general form they are called "Merkel trees". Filesystems aren't generally structured this way but, for example, git repositories are Merkel trees.