I'm sorry to see that there aren't that many success stories in here - currently I would view W10 v2004 as a revelation for my temporal dithering / subpixel rendering sensitivity. However, my experience is completely dependent on the Intel drivers.
I've got 7th gen Intel graphics in my laptop (HD 630) and I provided I use very old drivers I can use it all day. I have experimented with new Intel drivers (2018 - 2020) and they cause the same 'unable to focus', squiggly eye feeling that I had with Windows 1909, which will build to nausea and migraines if I continue. However, revert back to the oldest drivers I could find (Intel HD 21.20.16.4475) and the display is calm, easy on the eyes and I can use it all day on my XPS 9560.
I'm going to use this information to really push Intel to investigate.
I have also updated the Nvidia drivers of my onboard 1050Ti to the current version (26.21.14.4614) and I am experimenting with gaming on my laptop for 1 hour at a time, and have yet to get any symptoms - bear in mind this is the first time in 8 years I can game on a laptop.
Feeling boosted by all this, I went to work trying to get my brand new XPS 15 9500 to work (Intel UHD 630 on board). After days of experiments, I feel there is nothing that can be done to make this new integrated card work for me - it triggers crazy nausea, migraines and dizziness from working on it.
Overall I still can't quite believe I have a working setup, on good hardware, and a modern OS that is basically 'vanilla'. Really hope there are further success stories to come from v2004.