Universal print would be a lot more useful if it provided support for both Windows and macOS devices as many enterprises support both platforms.
Mac would be nice, iOS is really essential though. MacOS at least you can manage and secure enough to add to the internal network, iOS especially BYOD most organizations are putting in a wifi SSID that's walled off - but AirPlay is not easily configured in large organizations, without building multi-NIC bridge boxes in every site that spans your firewall. Universal Print would neatly solve that by allowing print to internal print servers while only needing internet access not internal network.