I also got annoyed with the Registry(*args, **kw) api and so I simplified it to just accept the package name. This is an incompatible change to the api but I can't imagine anyone was relying on the original version.
I tried to take this further and define an IRegistry that documented both the IDict and the zope.interface.interfaces.IComponents but unfortunately zope.interface does not provide any documentation of the component registry API. If zopefoundation/zope.interface#70 goes anywhere then we may revisit that to improve the registry documentation.
improve the registry documentation to cover usage as a dictionary
changelog for #2893