UPDATE:
So, I come bearing a pretty good update people. Hopefully, this can help a lot of you out here. It certainly helped me.
I have resolved the issue it seems, without reinstalling Windows, that is. And these were what I did (in order):
- Revo Uninstaller: I used Revo Uninstaller with advanced scanning to uninstall AI Suite III, cleanup leftover registries and files. Be sure to verify that you are only deleting registry entries and files related to AI Suite III. If you want to be safe, make a backup of your Windows install prior to doing any of these. In my case, however, I went a bit paranoid and overkill, so, I have also uninstalled with Revo Uninstaller everything else that came from ASUS. I had Armoury Crate installed as well, along with some AURA stuff. Basically, I purged my Windows out of anything that has any relation to ASUS. Then reboot.
- CCleaner: I used CCleaner to do custom clean and registry cleaner. In custom clean, I think you mostly wanted to clean for the "System", "Advanced", "Windows", and "Utilities" section. I again went a bit overkill since I see nothing to lose in wiping clean the other sections except. Be sure to read every tick boxes to understand what is going to be wiped if you select that option. For the registry cleaner, what I did was I ticked all boxes and run the scan and fix. Again, it is very important to read the entries to be sure that you are not altering anything system critical. But, you also have the option of backing up the registry changes with CCleaner anyway, and if you have backed up your system before, you should be more or less safe. Then reboot.
- Manual work: This involves going to task manager, stopping any tasks related to ASUS that is still running, and then going to services.msc to also do the same thing. Once this is done, I went to Program Files, Program Files (x86), and ProgramData to delete ASUS folder there. Again, be sure to only delete things related to ASUS, do not delete any mission-critical files. Then reboot.
- AI3Cleaner.exe: You can download the tool provided by ASUS via this drive link (https://drive.google.com/file/d/0Bz2VRRbLPrZnM0VyNkZ3SjhEdGM/view). It doesn't feel like it is doing anything, but I ran it once (as administrator) anyway for good measures. Then reboot.
- CCleaner (again): It should be noted that I did 1-4 prior to writing this asking for help post, as after doing 1-4, my issue still remains. I now repeated 2, but I ran CCleaner custom and registry cleaner multiple times until I saw nothing left. Nothing left to clean and no registry issue to fix. This may very well be a completely unnecessary step. Then reboot.
- Windows 10 in-place upgrade: Now, this is the one that changes everything for me. I used Media Creation Tool from Microsoft to download a Windows 10 .iso file and performed an in-place upgrade. This refreshes your Windows 10 installation but keeping all files and applications untouched.
Right after 6, I boot back into Windows, ran Cyberpunk 2077, and lo' and behold, the issue has completely disappeared. I am getting around 110 fps at 1440p ultra preset, my GPU is 100% utilized, CPU utilization is also higher, at around 40%! Performance now scales properly with different resolutions and presets.
Here, I reported everything I did to fix it, but keep in mind that not everything may be relevant. You can decide for yourself which step makes sense to you, which doesn't, which step to follow, and which to ignore. Other people have also reported that Armoury Crate is fine and only AI Suite III needs to be removed. I can't comment on this specifically, but it doesn't hurt to try and just remove AI Suite III instead of going ham like me and remove everything ASUS.
If you don't know how to do an in-place upgrade, check
https://answers.microsoft.com/en-us/windows/forum/windows_10-windows_install/how-to-perform-an-in-place-upgrade-with-windows-10/7f0b236e-3c6c-4913-9691-c4baa2a6190a
Else, you can also ask me about it!
Again, don't forget to make a backup should you do anything related to registries! I wish you all luck!
TLDR; If you are lazy and you only want to try out a possible fix quickly, I suggest removing AI Suite III with Revo Uninstaller advanced scan, run AICleaner.exe, and perform Windows 10 in-place upgrade. In my opinion, these are the steps that are actually meaningful.
