Yeah, they could do it with DNG (I suppose), but they don't really have any reason to do so (in their minds). Personally, I like open stuff, but they did not share my mindset, and I respected their posture.
If a camera company sells me a camera, I consider it a definite disadvantage, if I cannot open the Raw files until the software companies have updated their products. This is also a great way of forcing customers into the subscription models like Adobe offers.
So as a customer, I do criticize that they don't support more open formats.