Data Merge, CSV file containing column header named 'table'
A CSV file with a column header named 'table' will fail to import with 'Data Merge > Select Data Source.' No errors are given. The 'Data Merge' panel remains unpopulated.
Changing the header to something else, e.g. 'Table', will work.
Adobe InDesign 18.5 on Windows 10 and macOS Monterey. 18.4 behaves the same way.