The very real reality at the moment is the industry, the motion picture industry that Red markets and caters towards, is moving towards 4k. Also large sensor cameras have been more desirable for the majority of interchangeable systems.
Red made a very, very good decision by making the Scarlet X 4k and with it's current sensor size.
As mentioned above, you can shoot at 3k just fine on the Scarlet X if that was your target resolution workflow.
Dragon btw, is a very logical step into making a wonderful 4k debayer of a 5k S35 image with the promise of more latitude as well. Hence being a true(r) film alternative.
Technological advancement is progressive. Red doesn't like to go backwards.