We currently have intense income inequality in the world - pretty sure we can shave some off the top and the middle to help everyone live a healthier life.
That doesn’t mean that food production went up, or that more houses get built cheaper, or that new doctors are cloned, or anything of the sort.
It just means stocks went up.
Most of the economy is people providing stuff to other people, or working to import stuff. If people don’t work, you don’t get the stuff they provide.
To a certain extent you can sell off assets abroad and import stuff using a trade deficit. But that doesn’t work forever, and you can’t import haircuts or clean floors or construction labour or nurse shifts. At a certain point work is needed.
Some people have more money than they need, it can be removed from them - the intricacies of how they got that money should be very carefully considered when it comes to structuring how UBI would be funded - but they clearly have more money in absolute terms. And that wealth is transferable.
Also, in the western world, we have enough of everything. No one starves in America because there isn't enough corn, they starve because they don't have enough money to afford it - no one is homeless because no homes could be built, they're homeless because nobody wants to pay for the home to be built.
These are all solvable problems.
Now we can certainly say that "hey maybe if these guys all didn't have such a big mansion or as many cars everyone else would be better off", but you have to be explicit about that. It's about taking away things people like and to put that effort elsewhere.
Some ways are better than other, but this idea that the powerful can hide their power through accounting tricks alone is a failure to think at multiple layers of abstraction.
It's why this article is from the CBC, since Canada (while not perfect) is much better than the US in pursuing good things even if it hurts the powerful.