The sort options for Go FOLDERCONTENT menus only affect files; folders in the menus are always alphabetical.
(Folder dates are rarely meaningful, and folder sizes aren't calculated when building the menus, so folders are kept alphabetical. We could add separate options to sort the folders if needed, which would be better than having the file sort options apply to folders. I think people usually want folder alphabetical in those menus.)
sortdate - "Sorts files and folders in the generated list by timestamp."
In terms of my use case, I have a number of folders each containing a number of files (application builds). I'd like the folders sorted by reverse date so that the folder containing the most recently updated files (ie build) is shown at the top of the list.
If a folder-specific sort argument could be put on a feature request list somewhere, that'd be great!