That may work for very easy tasks like animation but nearly all apps I have worked on and continue to work on is not going to work as stateless. People expect that they will just continue off were they left in an app and for some apps, you can't fit all the state as query params.

It's just not possible to calculate most stateful things. It's interesting to me since I am currently working on a state manager where we have many "apps" on in the same app. The user needs to be able to switch between apps and only some state is going to be shared.

Thus, I need to store the state somewhere and it's not going to be in the url or in some calculated way since it's based of user selections.