Blockchain as the internet's underlying protocol introduces single-point-of-failure risks. If a dominant blockchain network suffers a critical flaw—such as a 51% attack, consensus failure, or smart contract vulnerability—entire ecosystems relying on it could collapse. Scalability bottlenecks may lead to network congestion, halting transactions. Centralization of mining power or node operators could undermine decentralization, creating exploitable choke points. Bugs in core protocols or governance disputes might freeze operations or erode trust. Unlike the current internet, where diverse protocols mitigate systemic risk, a blockchain-centric internet concentrates dependency. Redundancy, robust governance, and rigorous auditing are essential to minimize these risks, but no system is infallible. Overreliance on a single blockchain could amplify vulnerabilities, threatening the stability of a blockchain-based internet.