Yes the Honda stuff is extremely expensive. Figuring out exactly what was needed to install the Honda bags on my buddy's 2019 has been a nightmare, especially since the one lock body and wave key that was supposed to come with the bags themselves and didn't (why you only get one when you need two is beyond me), and has now been on backorder since April? We did order a second lock body. Zero mounting instructions. Zero instructions for putting anything together.When you price the 2021 NC luggage set, which might be around $2000 (US) if I remember right, the Givi stuff looks somewhat modestly price.
"Genuine Honda Accessories" is Japanese for you still need to buy two more accessories in order to install the first accessory you bought.
Were I to put hard bags on my NC I'd probably go Givi, but I'm a soft bags kinda guy so I don't have to worry about that kind of stuff.