The visual interface for workflow definition is more hassle than benefit. The majority of such applications' complexity is not in the sequencing of operations but in state management, expressions, data manipulation, parameter passing, and retry policies. None of this is visible in the diagram. So engineers have to use UI/DSL to design the flow, but then implement most of the complex logic in non strongly typed code as parameter passing is usually using a map.

Temporal represents all the business logic in one place in the programming language of your choice. All parameter passing is strongly typed.

I see people advocating visual representation for workflows. But if it is so great for programming in general, why they don't advocate the same for systems programming, for example? Linux kernel in JSON/XML anyone?