Let Users Make a Feedback before Download File
Depending on your Drupal coding skills I would use a custom form with a modal using the OpenModalDialogCommand. In the modal you can attach a form with a textarea and a submit button. On clicking the submit button the feedback from the textarea gets stored, the modal gets closed (CloseModalDialogCommand) and a BinaryFileResponse gets returned.

I don't know of any contributed modules that provide this functionality.

P.S. I am assuming that you are using Drupal 8 here.