> You always have to use setStore

This is a design choice, and explained in their docs:

    Separating the read and write capabilities of a store provides a valuable
    debugging advantage.

    This separation facilitates the tracking and control of the components that
    are accessing or changing the values.

> You need to learn its documentation. You always have to use setStore, and it has a weird syntax like `setStore("users", 2, "loggedIn", false)` and even pushing items to an array is weird.

It's optional, and incidentally quite expressive and powerful. But they also support mutable drafts out of the box.

    import { produce } from 'solid';

    setStore(produce(state => {
      state.users[2]?.loggedIn = false; 
    }))