Does Orbi Use HT160 Larger Channel Widths?

Well, first, what speeds do you get connected directly to the modem when you do a speed test? Just because you're paying for gigabit internet, and ostensibly have a plan which provides it, doesn't mean you're actually getting it. Problems could include network congestion, an older modem that isn't capable of your plan's speeds, multiple devices using bandwidth at the same time (so, in aggregate, you'd be getting close to the full speed, but any single device could only be getting a fraction of it at any given time).

Second, you can do a wired speed test via the Orbi router. Ideally, you want the testing device to be the only one connected and using any bandwidth, so no other devices connected via ethernet, and no devices connected via wifi. But you should get very comparable results doing wired speedtests when both connected directly to the modem and conected (via ethernet) to the router.

Third, you do a wireless speedtest. But here, there may be some degradation. There's overhead for wifi, your results will depend on the distance between your router and device, what materials are in between (walls, floors, electrical wiring, pipes, ducts, furniture, appliances, people), and what other devices are causing radio interference (neighbors' routers on the same channel, sometimes microwaves, baby monitors, etc.).

If step one gives you good results, and step two is comparable, but three is much worse, you could try respositioning your router/satellite(s)/devices, try finding a channel with less interference and specifying it (as opposed to using auto channel selection), making sure your microwave isn't in use while running the test, etc. You could also look at the wireless settings in the Orbi, and maybe consider performing a factory reset, reconfiguring the Orbi and a single device, then running the speedtest again.

Tech specs are here and you should be able to get in excess of gigabit speeds both on the backhaul between router and satellite(s), and over the (wired or wireless) connection between your device and the Orbi, though this will, of course, depend on network conditions, how many other devices are connected, etc. But the system is capable of giving you the speed you want.