This is very true, and may have seemed misleading. Although I should note that the frameworks are not "ObjC frameworks" per se, but rather the Cocoa/OPENSTEP f

This is very true, and may have seemed misleading. Although I should note that the frameworks are not "ObjC frameworks" per se, but rather the Cocoa/OPENSTEP frameworks—which are mirrored, for example, in Objective-C++, making them not exactly ObjC specific, philosophically. But you're absolutely right that this is the difference between being able to use Objective-C on Linux and being able to use Cocoa on Linux :P