Previously working .package files prevent launch after July 21st patch

After updating, my game no longer reliably launches with my existing cc collection. It worked immediately before updating.  Regular .package files would cause the game to not launch or give me an error when trying to launch the game. A good chunk of my mods folder was effected. I could uninstall the game or start with a new mods folder and have my game launch with my mods, then suddenly the same ones will cause the game to crash when launching again. 

The game will either give an error stating that required game data is missing or damaged, or the game silently exits before any game window appears.

It launches fine with no mods and with script mods. Always deleted localthumbcache and have my mods up to date. I have a very large mods folder, never had any issues like this before (57 gb).

For one affected hair, I downloaded a fresh copy from the creator. The fresh copy launched successfully when tested alone, while my previous copy still caused the launch failure.  I redownloaded a whole folder of cc that was giving me an error, and then another folder that was fine before started crashing. 

Everything was working perfectly before this update and I haven't been able to play since updating. From what I can tell this is mostly hair and clothing cc.  

I've tried repairing, uninstalling, new mods folder, etc.

Steps to reproduce

Generate a fresh The Sims 4 user folder.

Launch successfully without Mods.

Enable Custom Content and Mods, then close the game.

Place one affected CAS .package file in the generated Mods folder.

Confirm that the Mods folder contains only Resource.cfg and the one package.

Delete localthumbcache.package.

Attempt to launch the game.

Packs

All besides bust the dust & batuu

System information

Platform: Windows PC

Game version: Latest

Launcher: EA app