Silicon Valley “design languages” are languages exclusively for the designer to speak to the user. The user is not given an equivalently expressive language to speak back with: the Silicon valley designer believes that the user has nothing valuable to say beyond affirmations and grunts. A "design language" is a language of sermons: preachers do not tolerate interruption of their mass with questions and commentary.
I love this. The problem, as pointed out decades ago, is that there's no value to capital to develop these kinds of systems. They need totality, need to be the thing underpinning them. An operating system might be able to do it, but that would require standards, and companies don't have a profit motive to make them.