I don't follow why the money stock needs to equal total estimated wealth. Suppose I own a house with an estimated price 1 BTC, a car with estimated price 0.1 BTC, and some other stuff with estimated prices totaling 0.1 BTC. Further suppose there are ten of us and the average price estimates are the same as what I have. Our houses, cars, and other stuff total an estimated wealth of 12 BTC. It does not necessarily follow that we also need 12 BTC to support this situation. I suppose 1 BTC would be a floor, otherwise we could not expect the house to exchange at 1 BTC. But we might also be able to get along with 2 or 3 total BTC among the ten of us instead of 12 BTC. We don't need to be able to liquidate everything all at once. The money is an independent good itself with its own supply and demand. I recall doing a similar calculation where I estimated the total money in the world (not total wealth) and figured BTC would need to be like $100 USD to support all the exchange in the world. Maybe I was off by an order of magnitude, though.