Need to wait and see if AMD will allow the RX 400 & 500 series GPU cards to be able to support RSR via AMD GPU Driver in the future (Posted 5 days ago) : https://www.pcgamer.com/radeon-super-resolution-amd-rx-580/
The catch right now is that RSR is only available in drivers for Radeon RX 5000-series GPUs and above. That means anyone sporting an older GCN-based GPU, such as the popular RX 400- or 500-series—or even the ill-fated Radeon VII—is out of luck.