Hey xlr8r,I was right in my assessment that once the next version of Windows 10 was released that my mess would be right back. 21H1 removed my hard won intel drivers and put me right back on Microsoft drivers. Instead of fighting the battle again, I did what you did and installed a Renesas usb 3.0 add on card for my 3.0 devices..
Your case is somewhat different than mine. To get back functionality of your ports I would try this:
1. unplug all usb devices except KB and mouse in Renesas ports.
2. Remove all non present devices. There are several ways to do this, all listed here.
Cleanup orphan/hidden devicesThere's a script file there which I'm sure will work, but I just manually removed mine.
3. I think you are then going to have to remove all the USB host controllers and usb root hubs (2.0 and 3.0) EXCEPT for the Renesas ones. Make sure when you uninstall from device manager that you
also select to remove the drivers. Restart and Windows should reinstall the controllers and the hubs using Microsoft drivers. Then see if when you plug in a device it shows up using the correct host controller.
This won't get the intel drivers back but at least should get all your ports working again.
Hope this helps.