Your concerns about input events moving up and down the component tree seem misplaced. It’s what happens when you use React anyway (unless you’re only using local component state); putting these input values in the Redux store only makes things simpler.
As for the fact that it changes the state and adds noise to the log… these seem like aesthetic judgments on your part. Why is changing an input “noise”? It’s an important part of the data on the page.
No, it's a pretty valid concern. If you assume controlled inputs, and you also tend towards putting all your state into Redux, that's exactly a use case issue you can see - every keystroke would, in theory, require a full round-trip through the store and back to the component, and also causing at least a `mapState` call and comparison for every other connected component along the way.
Yes, if the keystrokes are not debounced it generates many actions. But my point is that concern about the ‘efficiency’ of moving events through components when using Redux is nothing compared to the byzantine way I had this implemented before using Redux. Trying to build forms in React without Redux or some other state solution, by just using setState and moving events and state up and down the component tree, will make you tear your hair out.
As for the fact that it changes the state and adds noise to the log… these seem like aesthetic judgments on your part. Why is changing an input “noise”? It’s an important part of the data on the page.