From initial playing around with mine, I would say the strength of the device (which the OS doesn't completely lean into yet, but I would bet improvements are in the works for visionOS 2) is the "spatial" part, and I suspect that's the whole reason for its emphasis in the marketing.
That is to say, imagine your terminal as a floating window, but you've also got other windows arranged around your home and office, not just clustered at a desk. Reminders floating near your fridge or break room, weather forecasts near the coatrack, calendar with upcoming events on a wall, Kindle or Books.app floating next to your couch...
Obviously it's a really, really expensive device (and a somewhat uncomfortable one) just to do that kind of thing with, but if you cross your eyes and stare into the future I think you can see the path towards much more refined devices that fill the role of letting you have "virtual stuff" in the same way that you might hang a clock on your wall today.