Anything you might want to do with a radio or IR device but don’t have specialized hardware for. It’s kind of a swiss knife/leatherman tool for short range communications standards.
I think of it as the browser dev tools of radio. Most people will have no use for it but it brings visibility and interactability in to an otherwise invisible world.
Logical NAND of a laptop featureset. Has things like IR, a subghz HDR, NFC+RFID, USB device support, iButton, and the like.
Some people get a lot of use out of it, but if you just saw that list of hardware and couldn't think of one area you'd apply it in, it's probably not going to be a useful device for you.