When creating reports in ArcMap 10.x, we were able to display the details section of a report using multiple columns that wrapped across the page, rather than a single column that extended to a new page. The inability to do that dramatically increases the total length of certain reports.
Adding the ability to utilize multiple columns and having the columns wrap across the page before moving to the next pages would be a great improvement to report building in ArcGIS Pro.
My current use case is building a street index for an overall larger, county wide Street/Address atlas. I have attached an example of the report from ArcMap 10.8.2 and an example from ArcGIS Pro 3.2.1.