In the Origin app, right-click on the gear icon next to the Play button and select "Repair".
Same is happening to me. I was loading up my main save I played just yesterday before the patch. I attempted to load it 3 more times before I went into offline mode to see if that maybe helps, it didn't. I then tried loading another save which also didn't work. Then I tried creating an entirely new save which resulted in the same issue I had a couple of times before now. None of the saves, or even creating a new one, work. I am stuck in a loading screen. Just to be sure that I wasn't rushing anything I was waiting for 3 minutes but nothing happened still. Just like OP it happened after the patch that fixed the excessive crashing. I have all EP's except for Discover University, and Snowy Escape. I have all GP's expect for Journey to Batuu. And Luxury Party, Cool Kitchen, Perfect Patio, Movie Hangout, Fitness, Spooky, Nifty Knitting, Vintage Glamour, Romantic Garden, and Laundry Day are all the Stuff Packs that I own. I am playing on a Mac as well.
Did you try repairing your game? It worked for me (Open your game library on origin, choose sims 4 and select “repair” under the cogwheel symbol.).
I have tried repairing the game a few times and nothing is working
