smittenkitten093 Since you've established that your mods and custom content are the problem, you'll need to test the content and update or remove anything that isn't working. Here's a list of mods and cc currently known to break CAS:
https://answers.ea.com/t5/Mods-CC-Issues/CAS-infinite-loading-screen-after-23-07-update/m-p/13898929#M64494
And here's a longer list of mods and cc broken in general:
https://answers.ea.com/t5/Mods-CC-Issues/Broken-Obsolete-and-Updated-Sims-4-Mods-1-108-July-23-2024-Game/td-p/13891143
Anything not on that list, you'll need to test yourself. If you still have a lot of files to sort through, the 50/50 method can make the process much more efficient.
https://modthesims.info/wiki.php?title=Game_Help:Finding_Problem_Custom_Content#The_50.25_Method