You can already run Planet Coaster 2 on DLSS 4. Officially supported by Nvidia. I've been running it for the last few days, it runs fine. It's a great improvement for image quality in Planet Coaster 2.
Just use the excellent DLSS swapper tool to swap the DLSS files out yourself. It's quick, easy and now supports DLSS4. It's good for all games, actually.
Google is your friend.
With this you can have DLSS4 up and running in Planet Coaster 2 in minutes.
A photo of Planet Coaster 2 running with DLSS version 3.7.20, the version the game ships with.
A photo showing Planet Coaster 2 running with the very latest version of DLSS, version 310.2.1
DLSS, version 310.2.1 is the very latest version, also known as DLSS4. Super resolution has the much nicer transformer AI model, giving a much cleaner picture.
With DLSS 310.2.1 (version 4) any card from the RTX 20 series and above can use the much improved transformer model for DLSS Super Resolution, to properly use the new frame generation feature of DLSS 4, you will need a 40 or 50 series card. For multi frame generation you need a 50 series card.
This tool is excellent for updating DLSS to different versions in any game, it saves having to wait for developers to update their game, you can do it quickly and easily yourself.
If you don't want to use a third party tool, you can use the DLSS override setting in your Nvidia settings up under the graphics tab, setting it to the latest version after selecting Planet Coaster 2, this will force the game to use the latest version of DLSS. Both ways give the same results, just up to personal preference
To use DLSS override or updating to the latest DLSS through DLSS swapper, you need to make sure your on the latest Nvidia driver.
All in all, you can be running DLSS 4 within minutes on Planet Coaster 2.
You will get lower FPS with DLSS 4 over DLSS 3. The base rendered frames will be lower, so a more aggressive DLSS setting might be needed to get the same FPS as before. This is because the new transformer model of DLSS 4 is quite a bit more computationally intense than DLSS 3's CNN model, 4x more runtime power is needed infact, meaning your GPU is having to do more work to run DLSS, leaving less room to run the game. You can make this shortfall up by using a more aggressive DLSS setting however, what you do get is a much improved image quality with much less ghosting. The lower overall performance is a well worth tradeoff though.