First of all, it does not "just happen" to be selectable. RAW contains information that is not available in a JPG or PNG , but which is crucial to a lot of serious photographers.

Second, the native raw images do include a ton of adjustments in brightness, contrast and color correction. All of which gets lost when you open the image file with apps provided from other companies than the camera vendor. Eg. open a Nikon-raw in NC Software and then in Lightroom. Big difference. Adobe has some profiles that get near the original result, but the Nikon raw standards often are better.

So DNG would absolutely be an advantage because then at least these color corrections could natively be implemented and not get lost in the process.