Absolutely: internal gear hubs are the only gears you can use with belts. They just tend to be substantially more expensive for the same amount of gears as a comparative derailleur. Internal gears also tend to have a higher friction than derailleur gears - the really good ones such as a Rohloff speedhub cost > 1000 EUR. Even a comparatively mundane Alfine 11 gear costs ~ 400-500 EUR. A pinion gear isn’t exactly cheap either.

In return you get a mostly maintenance free setup. It’s great, but I probably wouldn’t opt for it for a city commuter bike.