Points in case:
- Obviously supercooled.
- We do not get to see how much it dips with passenger. Hence it very likely only carries its own weight, which may be almost nothing.
This thing is no hover-board, it just looks like one. Levitating superconductors are nothing new. The only thing cool or noteworthy is the clever misdirection by Lexus.
Even if can carry a person, I don't they would want to show the result. The thing has no resistence, I doubt anyone could stay upright on it, or even get both feet on it at the same time, and if they did, it would not look cool and elegant.