It means that there is a request for enhancement concerning a direct binding to Vulkan that would use only a part of JOGL in order to avoid reinventing the wheel, for example the windowing system (including NEWT) and some classes to manage the contexts.
Yes, Vulkan is very low level and harder to use than OpenGL and OpenCL.
Personally, if Apple decides to drop OpenGL completely and to prevent the use of Vulkan, I'll give up supporting OS X. I'm not interested in supporting an API only for Apple devices and Apple operating systems.
Finally, of course we'll need much more contributors to make it happen and using Vulkan will require some efforts. Don't expect your softwares to "magically" support Vulkan without effort with something that would expose OpenGL but that would rely on Vulkan.