Had same issue did what this guy said:
Local Prefs should be at version 9
Typically is found in your documents folder (C:\Users\username\Documents, C:\Users\username\OneDrive\Documents,
C:\Program Files (x86)\Diablo IV\Data)
Normally in one of those folders depending on OS version and if you nuked your onedrive/documents folder it’ll appear in the game data folder then in whatever drive you installed it on.
I suggest backing it up or taking screenshots of your current settings if you had a ton of customizations and may forget (screenshots would be better cause the file is likely old/corrupted from all the updates I wouldn’t reuse it unless you had some weird bug happen where you could only run the game with the old version which would be highly unlikely probably would have other system issues going on).
Otherwise yeah exit the game and battle.net and purge (delete) that file relaunch bnet and d4 and it’ll act like its the first time setup of the game but it’ll get rid of the bugs like always staying on “custom” and such for the presets when you select any of the drop downs. Mine had originally patched and only had the ray tracing presets and the non ray tracing presets were completely gone from the drop down.
You just need the game to generate a fresh copy of this file, I recommend doing it whenever they make any changes to any of the options so like when season 4 comes with the zoom out option you probably want to nuke the file again to be safe, it tends to only add the new data but not purge old data in the file so it gets confused, it does no garbage cleanup or replacement of the file sadly even with a file verification/check, only way is to del it for it to generate a latest and greatest without the old data from previous versions inside of it.
I run a 7735hs 7600s mobile amd laptop gpu and it runs fine on medium or high 1080p 60fps though I actually prefer to leave RT off I prefer the old looks more. If anything just add some sharpening but no need for upscale or RT but that’s just my opinion.
I know plenty of other that use the same mobile or desktop gpus from nvidia and ati that “should run it” and most of it was resolved with latest drviers and deleting that LocalPrefs file with the game and bnet closed.