@Jeansoo - The card gets used the same on both versions, but they have different drivers. Frankly, I don't think things look so hot on either right now because Windows updates keeps messing with how graphics are handled on that side and the new Mac version has a number of bugs getting in the way that need to be worked out.
The biggest problem I have on both platforms is the screen ripples on me, as if there were a thousand tiny screen tears that appear and disappear in an instant, when I move the game camera around at certain zoom levels. If I had to choose, I would say my game looks/feels better on Windows right now. And the Mac version is still suffering from strange looking overlays on hair and blocky eyelashes.
They're both a pair of moving targets though, and hopefully things will improve in different ways on both sides. (note: I'm still on Mojave on the macOS and it's probably time to take the plunge into Catalina)
