Wealthy people would learn to structure their earnings to flow into businesses in other countries to avoid this wealth tax. This would reduce income tax in the United States. I would guess the overall effect would trend toward a net tax loss.
If you gave 40 million people an extra $15K per year to spend, the prices of the things those 40 million people buy would go up. The poverty threshold would rise.
There are many second order effects like this that are always ignored in simplistic analyses.
It’s never simple math like taking one number, moving it into another column, and problem is solved.