On the surface, the degree of which we deem certain realities as impossible or "unrealistic/fictive" merely is an indicator toward the discrepancy between the reality we are currently experiencing and that other reality. In other words, our thinking mind is constantly measuring the possibility of other realities depending on how close the resemblance to the one we are currently experiencing.
The starker a contrast the less likely we consider it, especially when our mind is mentally and emotionally stuck in this reality. By gradually detaching emotionally and mentally from our current reality we open ourselves up for drawing in information and aspects from other realities, hence bring them into this reality. Something that is then considered utterly new in this reality might be utterly ourdated in that other reality, yet for us "it" might be just the perfect creative solution for our world as we are experiencing it at that time.
Enjoy the interconnectedness,
Alex