My main disagreement with this line of thinking is that in today's global economy, you can no longer "produce" wealth. 50 years ago, there was a constant influx of wealth into the country (from other countries), and so this was looked at as "producing" wealth. There were always new markets to enter that were untapped, new resources to be discovered, etc. Most of the world was still considered to be "third world".
But with today's global economy, the number of new markets is declining. There are no new lands to be discovered and most of the oil, diamonds, gold, and other valuable natural resources have already been discovered. Unless we start expanding to other planets, the size of the total pie will not continue to increase.
The end result is that an increase in one person's wealth goes hand-and-hand with a decrease in someone else's wealth. The more wealth those on top have, the less wealth everyone else will have. If you look at statistics from the last 30 years, you will find that the global economy has followed this trend. The wealthiest people continue to get wealthier while the poor today are much poorer than they were.
Here's some stats for the United States:
