Making it possible to expose the dataset of a report as a read-only api, for example with DataAccessIntent =ReadOnly by default, would be interesting for reporting/BI solutions like Power BI, dataflows and others.

Reports (data items) have similar functionality to query objects but also support AL in triggers. One could make use of the power of data items and AL code to create powerful (and maybe also aggregated) datasets and consume them in the layouts (RDLC, Word, Excel) and on top of that also externally in Power BI and other tools.

One could even create a report and via AL coding base it on the dataset of a Query, combining the aggregation power of queries and the flexibility of report data items.

It's basically almost the same principle of the new Excel layouts in v20, but then one is not limited to Excel as the visualization tool. This would allow someone in Power BI, dataflows and other tools to build a proper (star/snowflake) data model, consuming the data from APIs (queries, pages and reports).