While the blockchain is clearly a distributed system, in a very real sense it is the antithesis of classical meanings of distributed computing in the sense that

While the blockchain is clearly a distributed system, in a very real sense it is the antithesis of classical meanings of distributed computing in the sense that cryptocurrencies are designed to escalate their level of difficulty so as to fend off being accelerated by distributed processing, the exact opposite of most distributed systems that are designed to explicitly harness, or at least collaterally benefit from, parallelism.