If the intended audience is non-technical users who don't know how to code, then it makes sense to allow them to do things without code. Essentially, you're acting as a declarative interface, where the user tells you what they want done, and they don't have to worry about how you do it at the code level.
But if the intended audience is technical, and users do know how to code, then in general what they really want is to write code more efficiently -- that is, write less boilerplate code -- not to have all the code abstracted away. Because they know that abstractions leak.
In the case of a service to build REST APIs, where the intended audience is more technical, my guess is that what most devs desire is not to introduce another service layer into their application, but to be able to easily generate all the boilerplate and then easily modify it to fit their use cases.