One question I don’t think you’ve answered: have you installed any mods?
Another question: what type of graphics card do you have? There are some known issues with AMD hardware.
Considering that you seem to be the only one reporting this issue, I suspect it’s not actually one of the DLCs. Those are popular enough that surely someone else would’ve encountered the same issue and reported it. The couple of issues with .pak files I’ve seen in the PC Bug reports section were fixed by validating the files via Steam.
Unfortunately, computers are individuals. I see this every day - our company has a couple dozen Fujitsu latops from the same factory batch, all installed from scratch by yours truly, and I’m experiencing at least three different behaviors of the same software on these supposedly identical machines. So the problem may in fact be in your computer, despite the fact that in theory, it should run the game perfectly well.