Working with bolt 5 beta 10.
The uploads: settings seems to be ignored entirely and files are uploaded to /uploads/ by default even if enabled is explicitly set to false. As far as I've been able to tell, all child keys are ignored.
filename_handling: "suffix" is also ignored. defaults to prefix.
I have no clue if management_controller works as expected, but I've set it to false.
the attach_files: true key is also ignored.
At this point file type fields cannot safely be used.
My result: emails submit without attachments and my uploads folder is flooded with files.