Ideas
Just following up after having done more experimentation. Rolling back to prior saves (including saves from prior days, from before the 9/24/25 update, and from prior in-game days) and then going through the graduation has not solved the problem. The situation remains exactly the same as before: as soon as the graduating Sim in DU completes graduation, the graduation photo generates in their inventory as blank.
To see if I could see anything specifically happening at the moment of generation, I had a graduating Sim's inventory open to the Sim-crafted Photographs category and the graduation photo sub-category at the moment of generation. I noticed that the second the graduation photo spawns into the inventory, it generates as black. But this only lasts for a fraction of a second, and then it turns white (as described previously). Not sure if that is relevant but figured I would mention it.
In terms of additional information for my save, I have the following packs and kits:
EPs: Businesses & Hobbies, City Living, Discover University, Eco Lifestyle, Enchanted by Nature, Get Famous, Get Together, Get to Work, Island Living, Seasons, Snowy Escape
GPs: Jungle Adventure, Outdoor Retreat, StrangerVille
SPs: Bowling Night, Crystal Creations, Home Chef Hustle, Luxury Party, My First Pet, Romantic Garden
Kits: Artist Studio, Blooming Rooms, Book Nook, Casanova Cave, Comfy Gamer, Cozy Bistro, Cozy Kitsch, Desert Luxe, Fashion Street, Grange Mudroom, Greenhouse Haven, Modern Luxe, Refined Living Room, Restoration Workshop, Riviera Retreat, Secret Sanctuary, Simtimates Collection
Free: Holiday Celebration
Also not sure if relevant, but the problem started after I installed Eco Lifestyle and Enchanted by Nature. Other than those and some Kits, I have not added anything to be game in the intervening time between when the graduation photos worked in this save with these Sims and now.
Did some more experimentation, and it is also affecting the Get Famous celebrity autograph pictures in my game. Same exact situation happens at the moment of object generation: celebrity autograph initially spawns as black, then shifts instants later to white. Playing previously with Get Famous (before the current bug started), I never had this issue and was able to get many celebrity autographs, including from the same celebrities that now spawn blank autographs.
If relevant, I can relate a prior thing which I noticed with the celebrity autographs (before the bug started occurring; this goes back at least 1 year). The initial situation of the autograph being displayed as black would happen when the object spawned, but then, when you would place the object on the wall, the texture would fill in. So it is possible that a less-severe issue of the same problem (texture matching to object) was happening even before the current bug, although it never actually resulted in an unusable object (just that you couldn't see what the autograph looked like when it was in your Sim's inventory before placement in Live Mode onto a wall).
Based on everyone else's stories, I'm guessing the exact same situation is happening for the HSY graduation photo, the LD memorial photo, the paint from reference paintings, and any other generated photo or decorative object where the game has to generate a texture to place inside an existing object. Hence why it isn't affecting photos that your Sim takes.
And I would also guess, based on a survey of timeline of reports of the bug first occurring, that rather than being linked to any specific pack which we might've installed, the problem goes back to no earlier than the August 19, 2025 patch (Patch 186). Although I could find instances of players reporting generated pictures being black prior to that, I could not find any incidents of the pictures being reported as generated white prior to then, and the number of incidents of white pictures just after the patch is where a lot of the reported bug activity has taken place. It therefore seems reasonable to believe that the August 19, 2025 Patch 186 is the cause of the current problem.