I see no point for Apple to make one because not even Window's Add/Remove feature truly uninstalls a program. There are still a lot of registry files, system files that remain after you uninstall the application. The same situation applies to mac os x. The only way to truly uninstall an App is to do a search in finder for all files related to a particular program and then deleting them all.
AppZapper and similar apps are ineffective in removing all files/folders associated with apps being deleted.
The only thorough method is manual deletion:I just tested a few of these, using Skype.app as the file to be deleted.
AppZapper found 4 items
AppCleaner found 6 items
AppDelete found 9 items
EasyFind found 16 items
Finder found 17 items
Apple software doesnt have all the dependency issues that Windows has and also doesnt have .dlls strewn all over the place (as well as all the entries in the registry), since it keeps the the bulk of programs in packages. Preference files and the like dont take much space, so they can be left alone, unless one really feels the need to remove all traces of a program. So, uninstalling a program with Apple merely requires deleting the program for all intents and purposes.
DLLs are executable code. It is not unheard of for different installed applications to require different versions of the same DLL. "Fun" can ensue when an application is launched while an incompatible version of a required DLL is in memory....
I never completely understood the issue with orphaned DLLs in Windows. Is it a disk space issue or is there a danger of the wrong DLL getting invoked by accident? Regardless, those files in Application Support on the Mac are probably harmless. But still, they do take up space.