I feel like you're intentionally playing semantic games, i.e. trolling, so let me tell you straight that I don't appreciate that.
The fact a central bank is a "human institution" is irrelevant. The fact blockchain is a "technology" is also in itself irrelevant. The point is that each concept necessitates characteristics that are irreconcilable. Most importantly a central bank can not function without central authority. The defining property of the blockchain is the decentralization of authority. Authority can not be simultaneously centralized and decentralized, and so the blockchain and the central bank are antithetical concepts.
The fact a central bank is a "human institution" is irrelevant. The fact blockchain is a "technology" is also in itself irrelevant. The point is that each concept necessitates characteristics that are irreconcilable. Most importantly a central bank can not function without central authority. The defining property of the blockchain is the decentralization of authority. Authority can not be simultaneously centralized and decentralized, and so the blockchain and the central bank are antithetical concepts.