Amazon QuickSight now provides an option for both author and readers the flexibility to use drag controller on table and pivot table. Authors and Readers can simply alter column width by dragging from cell, row header or column header from both parent and leaf level in case of pivot table.
This is a companion discussion topic for the original entry at https://aws.amazon.com/about-aws/whats-new/2022/06/amazon-quicksight-drag-controller-rows-columns-pivot-table/