Unfortunately, it's impossible for us to verify what parts of the demo are 'realistic'. Did they use assisting technologies (e.g. a wire rig)? Is anything repeatable, or are the components one-and-done?

The software industry has taught me how sneaky a demo can be ;). That's without considering Tesla's history of bonkers claims and sus demos (anyone else remember the bulletproof windows?).

Edit: Removed a rhetorical question about the demo. Apparently there was a live audience, so they couldn't have just made a very tiny Roadster haha.