There are plenty of programs that make 'GUI widgets' available for composition. They are all variations on the well known 'Microsoft Visio'-style interface that

There are plenty of programs that make 'GUI widgets' available for composition. They are all variations on the well known 'Microsoft Visio'-style interface that allows the drag'n drop creation of streams and networks of components, for various specific purposes. For instance, anyone graduating in physics doing an experiment that requires some electrical devices wired to up to each-other will be familiar with one such program (whose name escapes me at the moment). As soon as you become a power user, using the underlying language or something similar to a CLI beats using the GUI. Distinguishing 'GUI widgets' and the ways in which you can wire them together and then actually wiring them together takes more time than doing the same thing in a CLI, for experienced users. I don't see this ever being solved.