Allright, got some news. I found exactly why it is that Tpkd.sys doesn't work with newer builds of Windows.
Seeking through the Windows Event Viewer, I found this error:
"The PACE License Services service is marked as an interactive service. However, the system is configured to not allow interactive services. This service may not function properly."
Then I found out that: "Microsoft has removed the Interactive Services Detection Service on Windows 10 Version 1803."
https://kb.firedaemon.com/support/so...-and-session-0
More details about supported versions here:
http://batcmd.com/windows/10/services/ui0detect/
But it appears that upon upgrading from previous builds, that service still exists, which explains why my previous install from late 2017 that I upgrader to build 1909 or 1903 still worked with the driver.
Other users, if you're willing to, you could verify that by checking if you find "Interactive Services Detection" in your services list, and by checking your Windows version/build number.
So there must be a way, or a hack to get it back.
Microsoft support was very kind and attentionate until I asked for that... Now I've got two support people leaving the chat right away when exposing that. I guess it's a sensitive subject.
I'll try to hack a way to add it back.
This link says:
"Make sure that the UI0Detect.exe file exists in the %WinDir%\system32 folder. If this file is missing you can try to restore it from your Windows 10 installation media."
Then run: sc config UI0Detect start= demand
So I'm restoring this file right away and will try that. I'll be reporting back and spread this file and procedure widely if it works.
Edit: This file doesn't exist on my previous Windows install. Gotta boot off of my old legacy Windows install, to check out the event log from it.