The PnP-Monitor Lock (Standard) driver does not now allow the monitor to appear in the color management device list (Win10 Pro 1909 and 2004). I'm sure it did until a week or so ago, so something in Win10 has changed quite recently to prevent it. The result is ICC/ICM color profiles cannot be applied, the fix is to uninstall the PnP-Monitor Lock (Standard) driver and use the generic PnP monitor one instead. This is unfortunate if you want to blank the monitor when remotely accessed and use colour profiles.