Does Perspective-taking require change, and do atoms take perspective?

First, it's important to note that point-view Perspectives (Ppv) have anything to do with change as the theory of mind (ToM) research indicates. Children are born with their “root” perspective and don’t typically take the perspectives of others until they are around 4-5 years old. Thus, Ppv exists and then later, new Ppv are introduced. This has evolutionary benefits for survival. 
Certainly in practice, being able to change one’s Ppv is important. But fundamentally for Ppv to exist, it really only requires filtering information in a part-icular way. Thus, if I see a set of playing cards and focus on the numbers and another person is focused on the suits, that would be a part-iculate focus. If, hypothetically, a person could not see colors or did not recognize numbers. Therefore their focus was not chosen, but constrained by their life experience and genetics. Their construct of the cards would still be perspectival; even if that perspective never changed throughout their life. So choice and change is not necessary to Ppv. Again, in practice, it is important. 
Related to atoms, they are actually sensing (D) through interactions (R) their environment and changing their behavior accordingly (similarly as we do). The research [1] is actually utilizing these qubits as perspective “sensors” to tell them about particular internal aspects of the system at a tiny scale. Thus, even though change is not necessary, it is occurring at this level of scale not only for the atoms but also for the constraining perspective that is sometimes placed on them by researchers. 
In practice, and at a human scale, we see this lack of variance occurring all the time. In fact, it is the reason why awareness of Ppv provides such a lasting cognitive benefit. People get locked-in to their perspective (it becomes invariant). Without the assistance of metacognition, even though there are choices available, the invariance continues. So, while change and choice are important, they are not universally necessary as a fundamental ingredient of perspective. It only seems that way from those who are taking multiple perspectives.