I still think that CUE/other configuration languages are too complex for most developers. Once you're adding language-like features (inheritance, schema validation, or control flow), you're better off using a general purpose language like Typescript.

Pulumi might be moving away from pure Typescript constructs because it's difficult to compete against something like AWS CDK, which will always be better because (1) it's specific to one provider and (2) is a first-class citizen.