I agree. Although I do believe that the schema needs to be designed first class for writing / programming, before considering what render model and edit GUI will manipulate the schema. Making the app schema first class for writing, ensures that who ever read / writes the code can predict the app behaviour with ease.
I've seen multiple platforms do this the other way around and before as a result the GUI is in full control of the app schema and you end up with machine generated config which is hard to debug, reuse, review and edit.
While designing the app schema for Lowdefy [1], we are only implementing the app schema by coding it by hand - all the time (at least until all best good practices are established). This ensures that we always implement predictable defaults and that we make sure that developers only write the minimum config to be able to create an app. No unexplainable / magic paramaters in any the schema.
We also implemented a MongoDB like query model in the YAML (Lowdefy operators), and we are often surprised by the level of complex logic that developers construct with ease.
yaml + Power-FX