Hi, I have the same issue, I played on sunday and it was fine at 157 fps capped. And since monday 10/27 it feels like the game is capped at 30 fps...
I had done nothing in the meantime, I tried installing Nvidia's lastest drivers and it changed nothing.
I9 10850K , RTX 4070, 64 GB RAM...
Edit : issue was actually coming from a weird CPU bug. My CPU was capped at 2.8 GHz instead of 4.9 GHz. Somehow the only way to fix it was to set the number of processors to the max in msconfig, however this is not recommended, but I switched it back to default and CPU is working fine now