Why Saudi Arabia Is Building a Floating City

This sounds like yet another large scale immensely expensive vanity project to save the Saudi Arabian economy before oil inevitably is phased out. None of these projects will succeed, at least not to the degree that planners clearly want them to. Look at 'The Line', a plainly stupid idea for a city, as literally just changing its shape to a normal city shape (rough circle) would save countless billions. What's the benefit of the floating aspect of this city? Why not build all of it on land, and then dig a canal if you need water access? 

This will fail and billions will be wasted, after dismal setbacks this project will be silently canceled. Mark my words.