Thanks so much for investigating further! I tested previously with turning off the tone mapper entirely (again, in a blank project), but could not get any results that were close to the source texture. I saw many threads with people mentioning the tonemapper would cause this, but I’m starting to doubt that they were correct since I turned it off and it didn’t help at all.
In the in-game screenshot you provided, I think the reason it looks so extra blown-out compared to the original image in this post is due to auto exposure, since its enabled by default in new projects. I always disable auto-exposure in project settings, as a personal preference
I’m not a graphics/rendering expert so I’m gonna be honest i know very little about framebuffer, unfortunately 