I agree that there shouldn't be any people with that wealth, and so does the person you were responding to. But taking away 90% of people's money above a reasonable threshold is definitely not going to help those people become ultra rich. It would make becoming ultra rich more difficult, and instead spread the wealth across the wider population - decreasing wealth disparity.

And although there is almost certainly a better way possible, this method is relatively easy to implement and is an obvious improvement over our current situation. So we can just go ahead and do it while we continue to find consensus on a better system in the long run.

You seem to be arguing that taxing the rich is somehow bad because it isn't perfect. Your argument makes no sense. You are saying that taking their money helps them maintain a position of wealth. That makes no sense. Of course taking their money will make them less rich. Surely that's easy to understand.