Not that it isn’t a lot, but the 3.2 trillion figure is a total, not an average; that gives an average of only 8 billion per person. Going off Wealth Shown to Scale, Bezos’ wealth could be equally spread among at least 23 people, and they’d all still be in the top 400.
The linked article does provide calculations. The main assumption for such a short prediction appears to be that the rate of energy consumption will continue to grow exponentially, which to me seems unsustainable regardless of the production method.
Another workaround would be to use a different frontend, eg. Eternity on Android. https://old.beehaw.org/ also seems to not have the bug.