This bug (outdated udev rules that disables important features from nvidia cards: audio over hdmi, USB xHCI Host Controller and USB Type-C UCSI devices) is still present (or at least my file /etc/udev/rules.d/90-mhwd-prime-powermanagement.rules has not been updated).
If this is supposed to work only on new installations (but still i think that the two usb devices are still not enabled in the last mhwd-db version) then I think that we need to add an entry on the “Known issues and solutions” wiki, otherwise everyone who hasn’t a fresh installation from the new iso will keep this bug forever (or add a script in a new update that patches the current installations)