This was done at night like all large scale David Copperfield magic tricks, so it's more like someone else played a chord and said the dog did.
The same fans that blew downwards to create lift were likely first run to suck it in to the ramp, then reversed.
These demos were not performed by "daily driver" cars - they were multiple look alike props in a magic show, each optimised for the trick shot and not driver comfort or experience (if any driver(s) even took part).
That's a nice theory, but it is wrong.
The fans that are used to create suction do not create lift. The amount of air moved by those fans is way too small to create lift, the lift is entirely due to compressed air used as reaction mass.
On a tangent, I prefer this two year old locally garage built "flying boat" to Musks "maybe one day" car prop: https://www.youtube.com/watch?v=1ILbQHnHPnY
( FYI - there's a couple of Dutch boats down there ... )
On the front of cars you can actually buy and drive there is the McMurty Spierling an electric single seater with a fan generating more downforce then it weighs (can go upside down)
However neither the engine, nor anything else, is designed to operate upside down, so it wouldn't be able to do it for very long.
I imagine it must be able to do some comical cornering.
Edit: citation? Common sense. If it was real they'd have done everything they could to prove it. It's as real as Tesla's self driving taxis were a decade ago. How many more times will people get duped by this conman?
I want a citation this was real before I believe literal smoke and mirrors at night.