The 4K display is more universal than 1080p, because it allows you to scale 240p / 480p / 720p / 1080p resolutions with perfect pixel ratios, and what's more, the 4K pixel density also allows you to recreate the CRT phosphor mask, so 240p /480p content can look comparable to real CRT. When 1080p is upscaled correctly to 4K sharpness and clarity will look amazing (like 1080p dipslayd on 1920x1080 monitor),
Also, 1440p on 32-inch 4K even without upscaling is as big as a typical 1440p monitor
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, so IMHO even 1440p is usable if you only adjust the viewing distance.
There's just one problem to adress. Default upscaling (bilinear filtering) looks like crap, because it blurs the image. Nearest neighbour can scale the image with perfect sharpness, but the image will look pixelated because when pixels are scaled up, they look like squares (on native resolution displays, glowing pixels appear round to the human eye, therefore we dont see pixelation). Phosphor mask in reshade can adress this problem though.
You have a 1080p display, so I took screenshots in that resolution. Please view these scrreenshots in full screen (1:1), otherwise mask will be not aligned correctly on the second image. The first screenshot shows 480p upscaled to 1080p with bilinear filtering (standard upscaling). The first screenshot looks blurry, while the second looks sharp, and I ran the game at the same internal resolution of 480p.
bilinear filtering
Nearest neighbour + reshade filter
I can use the same method to upscale 720p / 1080p to 4K, and get sharp image, therefore 4K display can be used for both old games and new games.
Also you dont need RTX5090 to play games at 4K. Even RTX4070S already get an average of 60fps at 4K native. Add to that DLSS and FG, and if you don't hit the VRAM limit, even 4K games run amazingly well. I think 4070S might be even faster than the PS5Pro.