It is very weird, but I am 99.9% certain that it was caused by installing GeForce 442.19 drivers. I am unable to identify anything else that changed across all OSes except that. I avoid updating drivers unless I have an issue that requires it. I take the position if it is working to my satisfaction, leave it alone. It might not if I change something. GPU drivers are probably the only drivers I update, and even then it is seldom. If and when I do, it is generally to spot check for a bump in benchmark scores. I often end up going back to my original optimal driver because the performance was found to have been degraded by the newer version.
And, I am pretty confident it was not a Windows Update. I only allow updates on my laptop (used for work) and only one Windows 10 installation on the desktop. My Windows 7 and Windows 10 LTSC are kept pristine to focus on overclocked benching results exclusively. Security is totally irrelevant and Windows Updates are really handy at screwing things up. I stopped allowing them to be automatically installed probably 7 years ago. This problem affected all of them the same.
I noticed that it appeared that ClearType stopped working on all of them. Screen fonts were also looking kind of rough. I also noticed things were not right with the Windows color schemes on any of my OSes after installing 442.19. It was subtle, but there was too much white. Windows 7 normally has a pale gray instead of white and I noticed Windows 7 was taking on some of Windows 10 ugliness in that regard. As I poked around a little more, I also found Windows 7 started having TDR errors just running WEI with 442.19. So, I ran DDU on everything and SFC /scannow on everything. SFC found corruption on 3 of 4 Windows installations. After running SFC, I reinstalled a slightly older driver. Now have a look. Back in business. So, my hunch is that it was GeFarts driver cancer that caused it. It appears that the NVIDIOTS screwed something up.