Penso que o Returnal utiliza RT para acelerar a iluminação global e 3D audio. Sendo 1080p nativo, e utilizando TAA e checkerboarding, não deixa de ser impressionante o resultado final.
The PlayStation 5's RT hardware is used to accelerate global illumination queries, essentially speeding up a software-based system and not used for direct visual results. A similar system is used in Nvidia's RTXGI, so I'll be curious if this technology is repurposed in some way for Returnal - RTXGI is a part of Unreal Engine 4 now. Housemarque also shared that the hardware RT system in PlayStation 5 is also used to take the 3D audio in Returnal to the next level: audio environment queries are accelerated with hardware ray tracing support.