I think the real answer here is that the dev team doesn't care about User Experience as long as they can turn their failures into plot points.

The vast majority of the story of Shadowbringers was driven by the lack of flying mounts prior to story completion. The Mt. Gulg / Talos Repair and construction arc, the second half of Amh Araeng, early Il Mheg, almost the entirety of the Amaurot arc, and most of Rak'Tika. Lakeland was the only zone that didn't have some plot point driven by you being unable to fly without Eulmoran airships / Amaros.