Now, there are ways to handle all this with less code in React as well (for example, MobX), but the current de facto defaults with hooks and Redux create so. much. boilerplate. for. every. little. thing.
I like and use React on almost a daily basis but I'll admit it can definitely be overly verbose sometimes (at least WidgetFactoryFactory's aren't common like in some other languages). I know next to nothing about Svelte though, I'd be interested to see how it compares to React in a complex app and what the big tradoffs are.
I think it's safe to say React wins on ecosystem but loses on verbosity w.r.t Svelte.
For examples, here's a comparison implementing the same functionality using React hooks and Svelte: https://github.com/joshnuss/react-hooks-in-svelte
Now, there are ways to handle all this with less code in React as well (for example, MobX), but the current de facto defaults with hooks and Redux create so. much. boilerplate. for. every. little. thing.