Reactivity has a specific meaning in programming:

https://en.wikipedia.org/wiki/Reactive_programming

https://en.wikipedia.org/wiki/Functional_reactive_programmin...

Which I think React doesn't really fit. React is not about data streams, nor about inferred dependencies.

> Technically you could just getElementById and update it, but react has what I call a whole "reactivity engine" to do it for you.

I would call that "declarative", not "reactive".

https://en.wikipedia.org/wiki/Declarative_programming

The closest thing to reactivity React has are dependency arrays in `useCallback` but I'd say it's a stretch to call that reactive programming.

Compare it with SolidJS's data flow. https://docs.solidjs.com/ Also notice how "reactive" is all over their landing page while React doesn't mention "reactive" at all https://react.dev/