Just to keep you updated on the findings, while we try to compensate for the loss, that we have to deal with because "addFile" and "addFolder" are deprecated for "shortcuts".
1. A Shortcut shows to a user, even though the user does not have access to the source, users will see the shortcut, although the do not have access to the file, just because they have access to the folder
2. To avoid irritation one has to redesign the entire process that has been established for years within a short period of time. Yet one can not replace labels with shortcuts, the concepts to not relate to each other
3.This was not the only hurdle - fundamental changes were applied to the means for deploying apps script.
Does anybody know who is responsible for this in person? Check if he is bribed by Microsoft for creating such a mess.