I am an amateur and have not so good understanding of linear DNG. But I assume in general the relation to color space requires a color profile. Other it is not possible to correct representation in another programms/devices. The base for conversion is not present. In my modest opinion DNG must not be relate to any color space. Or it must be possible to choose a color profile during export, or probably use any one as default. Additionally it is unclear to me what is the difference to export to TIF and export to DNG with the specified color space? What is advantage of DNG in this case?
Moreover the default value “Wide Gamut” is causes really problem by post processing: