It’s one of the only ways I know of to make a Windows ToGo installation (equivalent of a Linux Live USB),
You can also use WinToUSB for that btw. Yet another option is to install Windows to a VHD file (using a virtual machine, or using Disk2VHD to convert an existing install), then copy it to your USB, and make it bootable using Ventoy. The latter option is more useful, since with Ventoy you could have multiple other Linux ISOs (or other OS/rescue images) all on a single, portable drive.