Very much in agreement with your comment.

Having system files in Dropbox as the source of truth, and symlinking to their canonical locations, is a poor workaround. Does the software work for you, or do you work for the software?

As another comment suggested, one can use cron and rsync to the Dropbox folder. This at least maintains the priority of the system files being where they should be.

Or, one can use any other software that respects and works for the user. Syncthing is great.