> I think as devs we often think of our site or application as the center of the user's universe

Jakob's law is a thing but I actually think in the case of GDS they are in the fairly rare position of perhaps being able to justify the hubris you speak of slightly.

Not only are they directly or indirectly responsible for the UI of a frankly staggering number of online services, they are also one of the most influential bodies - perhaps in the world - when it comes to this sort of thing.