BM: Immutable chain means no bugs, not ready to release immutable chains

BM just said when the telegraph group talked about system variability: There are currently only two systems, one is mutable and the other is immutable. All variable systems are concentrated in the hands of a few influential people, and immutable systems will likely eliminate political risk and be decentralized. For the immutable chain, I have a new consensus algorithm, but the current immutable system seems to have some problems, the immutable chain means no bugs, I am not ready to release the immutable chain.