Eye strain on Kubuntu but not on windows

I am facing issues with eye strain on Kubuntu 20.10 on a dual booted laptop(vostro 5401). This does not happen on windows 10. The issue also happened on other flavors before kubuntu like Ubuntu 20.04, kubuntu 20.04, Ubuntu 20.10 and other distros like Linux mint20.1 and fedora 33.

I think this is an issue with intel drivers and not fonts as it also happens when playing a video. Still I tried disabling font hinting and changing it to full, I also tried disabling anti-aliasing, changing it to greyscale but it didn't work.

I also tried:

1. Adding i915.enable_psr=0 to the line in /etc/default/grub but it didn't work(https://www.dell.com/community/Linux-General/XPS-13-7390-Ubuntu-Screen-flickering/td-p/7430121)
2. Adding this ppa(https://launchpad.net/~oibaf/+archive/ubuntu/graphics-drivers) for updated graphics driver but that didn't work either.
3. Changing distributions as mentioned above
4. On Ubuntu 20.04, I tried the 5.8 hwe kernel, the 5.4 generic lts kernel and the 5.6 oem kernel but neither of them fixed the issue
5. Since the issue doesn't happen on windows, I tried copying windows' icc color profile to linux and switching to that but that didn't fix the eye strain either.
6. Tried changing refresh rate from 60 Hz to 48 Hz and to 56 Hz
7. Tried changing compositor settings in kde(like switching to opengl 3.1, turning off vsync, changing scale method to smooth)
8. Increasing and decreasing gamma through xgamma and through kde settings.
9. Switching to darkmode, changing wallpaper,adjusting brightness, turning on nightmode(nightmode is off in windows).
10. Switching to intel-media-va-driver-non-free driver instead of intel-media-va-driver.

Graphics part of inxi -Fxz :

Graphics:  Device-1: Intel Iris Plus Graphics G1 vendor: Dell driver: i915 v: kernel bus ID: 00:02.0 
           Device-2: NVIDIA GP108M [GeForce MX330] driver: nvidia v: 450.102.04 bus ID: 01:00.0 
           Device-3: Realtek Integrated_Webcam_HD type: USB driver: uvcvideo bus ID: 3-6:3 
           Display: x11 server: X.Org 1.20.9 driver: modesetting,nvidia unloaded: fbdev,nouveau,vesa 
           resolution: 1920x1080~60Hz 
           OpenGL: renderer: Mesa Intel UHD Graphics (ICL GT1) v: 4.6 Mesa 20.2.6 direct render: Yes

Just want to be clear, you are not crazy and intel eye strain is real. Its not related to blue light, its not related to color temperature, its not related to gamma. Its something more serious. At the begining I thought it is PWM backlight frequency, but then after some time when I left linux and went to OS X I got back to linux with lenovo carbon X1 7th edition. This suppose to be ideal laptop for linux, but it has intel GPU. And i'm experiencing the same eye strain. It literally kicks more or less immediately.

What do we know about this issue:

• Intel has been trying to identify what is the problem, but failed to come replicate the issue using objective means. For this reason they have stopped it and perhaps called at an "subjective issue"
• Other folks in forums are trying to highligh that it might be an issue with "dithering", which I'm not aware what it is and it is hard to control.

My advice for you is - you have two cards - one intel another nvidia. Try to force your device to always use nvidia hardware and disable intel GPU. Maybe this can be done in bios.