I mean, you can easily cover up the hole with a sliding door pretty quickly after dropping, or, as someone else mentioned, raise fences during the process.
This is far from the hardest problem to solve in the video.
I'm just pointing out that the flaw is egregious. PR videos are supposed to give people a view of the future, suspend disbelief for a minute. This just looks like something slapped together by an intern told to "put some future cars in a tunnel"
A damn disappointment for something hyped a while back from Musk himself. He should learn from Hollywood, movie trailers are far more important than the movie itself when public interest is involved.
This is obviously just a marketing video, but that isn't a very hard problem to solve. The bigger issue is building an enormous underground highway network under an existing city.
I was too busy noticing how there was no contention between the newly raised car leaving the platform and a new car driving into the platform, or the endless line of cars queueing to be raised or lowered, or the amount of time it would take for a car to make it in or out at rush hour, or brain sizzles
Do you really think that no one, not even Elon did notice? I would rather assume, that for this concept video they considered this detail as non-essential and the actual entry points would look quite differently (and safer) than displayed. They most certainly would be different to those "parking spots" shown in the video.
So you raise a fence around it (stored on the sides, underground of course), or slide a roof in (once again, stored below the surface) to prevent anyone from going in even if they wanted to. This doesn't sound like a biggie to me.
And (most?) new minivans nowadays. And most cars have power windows as well. And most supermarkets have sliding doors as well. And probably most garages in the suburbs have automatic doors. This is actually run of the mill technology.
The easiest solution is to make it a covered "garage" with doors on both sides then the hole is always covered. But that doesn't look as good on a promotional video.
There's a sidewalk I walk down, it's quite narrow and runs along a shoulderless road with a steady stream of cars whizzing by at 50 miles an hour. I think to myself 'how much more or less dangerous is this than walking along the edge of the Grand Canyon? One misstep and I'm toast. One misstep from one of those cars and I'm toast.'
We have a hardwired respect for heights, but at no time in our evolutionary history did we ever have to deal with the kind of speed cars move at. So we look at a 10 foot deep unprotected hole in the ground and instantly think 'Hey, that's a hazard', but we don't give nearly enough consideration to speed, and as such 2 million people each year who are killed and injured in US motor vehicle accidents, and we just sort of shrug our shoulders.
This is far from the hardest problem to solve in the video.