I'm voting disagree because as KarenRei noted the point of the elevator idea is to be able to use the street. That's owned and controlled by municipalities.
If you want to take up more space there are plenty more options.
And, jkn, yes the spaces would need permanent barriers, but the video was just a video. Putting a barrier would have blocked the view of the cars going up and down and made for worse visuals. The barriers themselves would be a trivial matter.
Besides, they've barely started working on the fundamental tunneling cost challenge, let alone the skates and elevator logistics.
BEVs can allow for smaller tunnels
Smaller tunnels and X allow for cheap tunnels
Cheap tunnels allow for more tunnels.
More tunnels and Y allow for better urban transportation in dense cities.
We don't even know if X will be possible. And we don't know what transportation will be like by the time X is achieved, and whatever it's like could affect Y.