What does RAW really mean then? Couldn't they simply redefine what RAW means to create a standard that can include proprietary technology? Like why not define it as including a spectral response?
(Eg Nikon's format is 'NEF', Canon's is 'CR3', and so on, named after the file extensions.)
I don't know if DNG can contain (optional) spectral response information, but camera makers were traditionally not enthused about sharing such information, or for that matter other information they put in their various raw formats. Nikon famously 'encrypted' some NEF information at one point (which was promptly broken by third party tools).