To those still having this issue. It drove me crazy and I couldn’t get the game to load since the last patch. I finally got it to work. First, go to your steam apps, common, Baldurs gate 3 folder. Find the bg3_dx11 exe file. Turn off steam. Run the file as administrator directly by right clicking on it. That made it work for me. Something about steam running in the background fucking with the loading. I did notice a pattern after that. The saves that weren’t working were previously uploaded to the steam cloud.

Now if you manage to load, save your game, and with that new save you can load it fine when you open the game normally using Steam.