Maybe every example I've seen of RxJS is doing it wrong, but I've not seen a usage of RxJS that wasn't:

a) Over-engineered and an entirely unnecessary level of abstraction and flow control for a web app

and

b) A total spaghetti mess of event handling code all over the place and no way to tell what the flow of events is and always having to hunt down difficult to debug issues as a result.

RxJS may be neat, but it's definitely architecture astronaut territory.