Okay, I'll bite. Analogies are not really helpful for software development. Comparing software development with building a house doesn't work and this comparison with foods doesn't work either. The problem is not in your mocks or your layers. Software development is about translating prose into code. Given that, it doesn't really matter if your shell is imperative or reactive because your job is translation not creation.

I had a feeling something was going astray when the examples were primarily about data access and I/O. Reactive is (at best) a framework for handling streams and events. CRUD events aren't a great place to start because you're only showing the happy path. What about sequencing? What about retry? What about conflict? I'm not questioning your concept; it's the application.

Reactive isn't a translation technique which is ultimately why these analogies fail. Sometimes I wish software engineers could have a Roy Fielding/REST moment where someone comes along and clarifies the purpose of software engineering by pointing out the fact that everything you need already exists. In lieu of that, I'm sure that people smarter than me will eventually abstract away the reactive boilerplate behind some language keywords because the alternative (i.e. more data access and service endpoint examples) is really tiresome.