Thanks for the reply. One thing I love about Flutter is that it's doing tremendous job under the hood to decide what parts of the widget tree is actually need rerendering. I might be wrong, but that's probably the major aspect of their widget tree system design. As a developer I focus mostly on the expressing of the UI via widget tree, and if I follow official examples and tutorials and do not invent the wheel, than it yield optimal performance.

If I understood your comment correctly, in SwiftUI developer should learn a lot of stuff to make re-rendering upon state change efficient?