I'm unable to access any households, even without mods or CC

I had this issue too! Check to see if your save files are still contained in the EA folder (Documents > Electronic Arts > The Sims 4 > Saves). For some reason, all my save files were wiped after the newest update, but I was able to find some of them in the old Origin folder (Program Files > Origin Games > The Sims 4 > Saves), and copy/paste them into the saves folder stored in the EA folder. I hope this helps, and if not, I hope someone more knowledgeable can help you! Good luck 🤞🏼