Are you sure you watched the right video? He brought up some pretty important points about what's wrong with a line shaped city in general. For example, a city can't rely on just a couple train and tram tracks. And also how bad the living conditions would be in such a city, everything is cramped and there is barely any natural light on the lower levels.

Yea, he just don't know anything about the project, so just speculating like everyone else ..every question or concern is already answered in their official twitter account even the bird hitting the walls concern

People don't know that these Mirror Glass Walls actually take 90% of the light indoors like any normal window but reflect the heat and ultraviolet rays .. so low levels will see normal morning except for the pillars of course ..

The hyperloop is actually designed for end-to-end and half-to-end travel.. travel within districts can be anything from electric golf carts/bicycles/metro to expensive stuff like flying cars for rich people

Also, everyone within the LINE will live at least 200m above the ground.. the ground level and the first floors is dedicated for services like restaurants and open spaces

As for the cost.. the already estimated the cost and signed a 1.3 Trillion dollar contract with chinese company to build the whole Line .. it is expected to finish in 2045 but we will be able to see Marina part completed in 2030 8 years from now ..