Contributors here are all end-users just like you. We have access to the same information.
I fully understand that higher screen resolutions will reduce the potential frame rate. Apple do indeed have a 5K monitor - this being the very expensive (professional) Studio Display. The specifications for the iPad Pro M5 (my example here) are arguably potentially clearer than the stated specifications for the much older iPad Pro M2.
If you require additional information you would be best advised to seek assistance directly from Apple Support. You can contact the Support Team using the Support link at top-right or bottom-left of this page.
Alternatively, you can initiate and manage your support cases from Apple devices using the excellent Apple Support App. If not already installed, the App can be downloaded from the App Store:
https://apps.apple.com/app/apple-support/id1130498044