Are Unicode blocks important for implementations of Unicode?
It may be surprising, but usually they are not. What matters for implementations of Unicode are the properties for characters. Those are obtained from other data files in the Unicode Character Database, and don’t depend on blocks, per se. In particular, since block identity is not exactly correlated with script identity, it is much better to rely on Scripts.txt when implementing an operation that depends on script identity for a character. Blocks are sometimes convenient for display of characters, as for a character picker application. But even when expressing such thing as the supported repertoire for an application, it is generally better to express that in terms of explicit ranges of assigned characters, rather than just in terms of blocks.
