Thanks for the update but this was never even a story to begin with, the text was a trademarked accreditation that the console can output 4K within a certain standard. Its just a badge to say "we do this fing right" (according to a test/body they created). Its just willy-waving.
It was obvious it was gonna be 4k on PS5 anyway, just certain people from discord trying to stir things up. Probably not fully 4k for PS4 pro though, their upscaling solution seems fine for that.
If it really turns out 4k on PS4 it will look like shit
If it really turns out 4k on PS4 Pro it will look like shit but somewhat playable
When it is 4k on PS5 it will still look like shit, because its ubisoft