In my “quest” to building a great state management solution I tried playing around with observables and operators as well. While not as sophisticated as Elf, I had a simple state management with the idea of “useObservable” hook.
But in this particular case I tried keeping things as simple as possible. The user of the func doesn’t even know that the state is a BehaviorSubject - using Rxjs is an implementation detail. I have the same func implemented without Rxjs, it was just easier for the article.