Too much "image sharpening" in the driver options. Disable it or change to minimum (10% is the minimum i think) if you are using adrenalin 2020. the Witcher 3 also have that option in game, so it accumulates together.
Have exactly same problem, everything looks as pixelated. I noticed that problem started after I updated from Adrenaline 2019 to Adrenaline 2020.
Driver: Radeon Adrenaline 20.4.2
(Radeon Image Sharpening is disabled)
That doesn't fix it, it's really a AMD problem and they keep deleting my posts while not saying anything bad, just the truth...
And for me is there since I ever changed from my old GTX570 to AMD Asus Strix RX480 so, a few years ago and even while loading windows the middle dots are already pixelated compared to Nvidia they are perfect dots...
ps: Also applying better AA disguises the problem better but doesn't fix it either and at a big cost of performance :(.