Orbi satellites

Probably because it's intended to be for home/residential use, and the vast majority of people can be sufficiently served by a router and three satellites. For use cases larger than that, particularly businesses cases, users might be better served with commercial-grade hardware.

It's also possible they wanted to limit the number of satellites it can support to prevent users, particularly ones in apartments, from all sharing one connection, rather than each subscribing to their own service.

Just a couple guesses.