You might be in luck. My 2080Ti can run ~68fps with near-max settings at 1440p, no resolution-scaling necessary. (For me, "near-max" means nearly all settings maxed out, except for shadows and clouds downgraded from "ultra" to "high." The difference is barely noticeable.) The issue is CPU/GPU combos that normally chew through 1080p/60fps content shouldn't necessarily expect that with this port, at least not in its current "day one" patch state.
In the higher-end case, 1440p isn't so bad (though nowhere near the 80-90fps I might expect on avg), but 4K is rough. Really,
my Ars article digs into my specific findings from two different systems, and you may be able to triangulate your use case better from there.