I don't see anything in common with Redux or contexts.

No libraries. No higher order components. No concepts to learn. No weird rules. No complex tracing of props and trying to work out why state updates were not triggered, or were triggered.

Redux is one of the most painful software development experiences I have had.

Just the thought of using Redux fills me with dread.

The event code above simply sends a message directly between components - that's nothing at all like Redux.

Can you describe how the above is like Redux?