The UITextView.allowedWritingToolsResultOptions has no effect to how "Writing Tools" feature works. When it is set to empty, it still offer all options in the Writing Tools popup dialog. The result is that it is not possible to limit output results to eg. only plain text, or disable tables in output.
let textView = UITextView()
textView.isEditable = true
textView.writingToolsBehavior = .complete
textView.allowedWritingToolsResultOptions = []
resulting Writing Tools has all options available. I Tested with TextKit1 and TextKit 2 setup.
tested on iPadOS 18.1 beta (22B5069a) Report: FB15429824