I think the difference is that instead of shipping a modified copy of the software, you ship a "patch" which fixes the software. That was very common years ago, whole markets existed for providing improved functionality of some portion of various OS's (macos, dos, s390, etc) via hooking and patching.
Of course its seems that that freedom is now restricted as well, but that is a fairly recent development that can be laid at the feet of the DRM advocates.
Of course its seems that that freedom is now restricted as well, but that is a fairly recent development that can be laid at the feet of the DRM advocates.