I agree that those formats would be nice for people doing movie sound tracks. But I think the future is going to be ambisonics, currently gaining favor in gaming/VR, but also better for music. For one thing, it will adapt to the listener’s speaker configuration, when it finally catches on in the world of consumer electronics. I expect this to happen because of gamers. Certainly there are a lot of 7.1 systems out there, as it’s almost standard on computers, but I wonder how many people actually have that setup.
I don’t know how much effort it would take Steinberg to do this. I know they’re working on ambisonics. Mathematically, all these formats can be authentically served by converting from an ambisonic source. (Preferably at least 2nd order.)