With TAA antialiasing on (it is the default) and using the “render scaling” slider to set your rendering resolution separately from the screen, results are in my opinion quite nice – and it’s a great way to trade off between GPU render time and quality.
I have a 4K (2160p) screen which I have set to 70% render scaling, which means it renders the simulation slightly higher than 1440p, then scales it up to 2160p and combines it with any menu rendering directly at 2160p. I find this looks really nice, though I haven’t compared it native rendering on a 1440p or 1080p monitor.