OData causes massive data load (Especially with nested Expand)

To improve OData performance in Power BI, avoid using nested $expand as it leads to large and complex backend queries that significantly slow down data loading. Instead, load related tables separately and merge them within Power Query. Always use $select explicitly not just for the main table but also within expanded entities to limit the number of fields retrieved. Applying $filter early in the query helps reduce the number of rows before they reach Power BI. If available, it's better to use the Dataverse connector, which is optimized for performance and handles queries more efficiently than OData. Additionally, turning off background data previews in Power BI can prevent unnecessary data loading during report development.