I agree with this. Blockchains are pretty much a novel subset of cryptography, and I expect the most interesting protocols/applications that get called "crypto" in the next ten years are going to make heavy use of both blockchains and other new forms of cryptography (ZKPs, MPC....). There will continue to be a rift between "purist crypto" and "mainstream/enterprise crypto" but it's the purist vs enterprise divide that will matter, not blockchains vs cryptography.