not really, RAW is NOT just a raw sensor dump straight from the hw into a file.

its a full fledged format, that contains the extensive metadata already in the exif formats including vendor blocks etc, and then its the sensor readout, which is relatively similar between nearly all sensors, theres certainly not many types, considering you can express the bayer pattern. This can all be expressed in DNG, and would NOT need to be an "extra" on top of "raw".

and indeed, some camera vendors do in fact do this.