New Relic has introduced a new Cardinality Management UI to help users diagnose and solve metric cardinality issues, allowing them to view account usage over time, get a metric-level breakdown, and prune high cardinality attributes to free up cardinality budget. The feature aims to prevent visual data gaps in time series charts and provide more control over cardinality. With the new Cardinality Management UI, users can easily manage their cardinality, understand which metrics are driving the most usage, and dive deeper into a metric's attributes to make informed decisions about data management.