often times you will have requirements that the documents you release be digitally searchable and so in these cases, this would not be an option
One fun thing I encountered from local government is releasing files with potato quality resolution and not considering the page size.
I had a FOI request that returned mainly Arch D sized drawings but they were in a 94 DPI PDF rendered as letter sized. It was a fun conversation trying to explain to an annoyed city employee that putting those large drawings in a 94 DPI letter size page effectively made it 30-ish DPI.
It's not hard to imagine some powerful LLMs being able to undo some light redactions that are deducible based on context