Using objects in the depenciess array of useEffect can lead to unwanted calls. As the check to run is referential, if the object reference changes (without any values inside changing), this will lead to the useEffect running. This will happen if using an object from props, for example.
However, there are a couple times where it's okay as long as you're aware. The object reference inside of a useState doesn't change until its setter is called. If the setter is called at all (even with the same object or using the current state value), it will update the reference.