The WebDAV package included their (they = Synology) old calendar server. Then they have created a separate Calendar package – so why use the old WebDAV package (without calendar UI) when they have now a real Calendar package available? I also guess that WebDAV calendars won’t get much support if there’s an active Calendar package which is actively maintained.
Do you see any reasons to recommend their old WebDAV package instead of their new Calendar pacakge?