The sentence makes it sounds like Cassandra and Scylla are slow for writes, which isn't the case at all. It's just that writes require a bit less I/O. Reads are

The sentence makes it sounds like Cassandra and Scylla are slow for writes, which isn't the case at all. It's just that writes require a bit less I/O. Reads are still very fast. If reads were slow, nobody would use Cassandra and Scylla for the purposes that they're being used for.