This is a bit stupid, because if the global wealth goes to 4600 trillion, you will be only needing 0.0045 BTC, so 140$ will make you a millioane.
In the end, we have seen so many predictions of this style, which make a snapshot and miss many parts of the supply-demand and inflation equation. It's like predictions of when bitcoin will reach a million, which is hard enough to get right, but the most telling thing will be what you can buy with a million by then, which at the rate we're going will be much less than it is now.
In the end, for me the 'power' of bitcoin comes down to the fact that if you accumulate as much as you can without obsessing about numbers or dates, you will be much better off in the future than if you don't accumulate.