I mean, you get more performance with a lower resolution, but, you're also losing image quality at a lesser resolution (even worse running a non-native resolution). So it depends on what you mean by 'best'.
The review I'm getting the info from was linked in this thread a couple of times already (techpowerup's PL review).
If your threshold is 60 FPS at 4K (like Rainless, the res)... the 4090 is the only card over 60 FPS at default Ultra settings... 4080 is 52 FPS. So it depends on what you mean by 'without any problems'. Below 60 FPS is typically a 'problem' for many. Worth mentioning, that's WITHOUT ray tracing. Enable RT without DLSS and those same users deem it unplayable (even at 2560x1440) on a 4090 (36 FPS at 4K UHD).1440p but if you own a 4080 or a 4090 no matter what setting you set it at in should play without any problems just my opinion.
The review I'm getting the info from was linked in this thread a couple of times already (techpowerup's PL review).