Issue occurring here on a 1070. No AA, no RTX. I tried switching to DX11 and the ones in my immediate view seemed to stop flashing, but I have not played enough yet to determine if it fully resolved the issue. The flickering was not affected by any other graphics setting that I tried prior to that.
One major area of concern I had was in Torghast (I want to say on Floor 4 of the special Jaina one, but I ran that and Coldheart back to back and they blurred together a bit). The floor used one of the tilesets with lava/fire. Whatever lighting effect said tileset used that this bug affects appears to be used on the entire viewable area on this floor. Because of the orange/red color used by this tileset, this resulted in my entire screen rapidly flashing between white and orange multiple times per second for almost the entire time I was on the floor. Given the intensity of the flashing, I would be incredibly concerned for any unfortunate players with epilepsy as it seems quite likely that it could trigger a seizure. I almost had to leave Torghast entirely before I finished the floor because it began causing my eyes actual pain to keep looking at.