There is no way to take anything like that. Net worth is quite similar with me saying you are worth 1 billion dollars, but you have zero money in the bank. What do you take, super-rich billionaire person?

Because that would involve seizing assets? The parent meant it's not "real" in the simple-minded sense that people think it is: the average person imagines Elon Musk and other billionaires have a checking account that keeps increasing by tens of thousands of dollars per second because that's the only frame of reference they have. The reality is the wealth is mostly tied up in assets that ain't exactly liquid. Yes yes, they apparently have access to this supposed infinite money glitch where banks will endlessly loan them money without requiring interest payments (which would require liquidating assets for payment and therefore triggering a taxable event, the very thing people think never happens for billionaires). But the fact of the matter is the wealth isn't money in a bank, and therefore not "real" in the sense the parent was referring to. But it is at the same time something they would miss if it was just "taken away", much the same way you'd miss the numbers in your 401k if voters decided you had a few too many millions saved up for retirement.