My wife and I had these issues horribly for the first 3 days. Our FPS was effectively cut in half, or worse. Standing in Valdrakken became a 30fps experience rather than our usual 80+. Then, with one of the hotfixes, my fps went back to normal, and I haven’t had any (new) fps issues since. The only major thing we did on our end to alleviate ‘some’ of the issues and crashing was to clear our shader cache from within the AMD Adrenaline control panel.
Other than that, I can’t say for certain why your issues haven’t cleared but myself, and many others, have reported that they have. My wife and I are both on Windows 11 with the 23.4.3 drivers. I have a 7900xt and she has a 5700xt, and for both GPU generations the issues have, for the most part, resolved.
Other than that, there is a very specific graphical issue dealing with skybox LOD that Blizz said they have a fix in testing. Odd FPS capping behavior - #28 by Drakuloth