If 20% are the entire tax base and the other 80% are supported by that tax base then explain how the 20% are not supplying far more than they get.
Everybody "supplies" something. Even though cops, firemen and teachers don't put any products on the shelves and contribute to GDP, they still supply a service.
So now the question becomes, how much should producers of items for sale be rewarded, and how much should workers that do other useful stuff be rewarded?
Let's say you are paid $30,000 for working 40 hours/week at producing 1000 widgets. Then, technological advancements make you 5x more productive over that same 40 hours, so you now produce 5000 widgets. (This is basically my 80%/20% scenario here.) Here is what is going to happen:
1) Ownership isn't going to give you a raise for being 5x more productive. You still work 40 hours/week, and you can be replaced.
2) If demand for widgets hasn't gone up, 4 of your co-workers are going to lose their jobs.
3) Ownership is going to pocket the $120,000 in saved labor costs.
Now 4 unemployed workers need something to do, yet there are no private sector jobs available. Technology is making labor more and more obsolete.
Nobody is looking to tax
you more - you still only make $30,000. You aren't the bottleneck. It is
ownership that would be expected to pay the new taxes, because they are the ones capturing all of the income that used to go to labor. And don't cry for ownership, because even if they are forced to hand over a lot of their profits, they are still coming out ahead. The money to be redistributed represents labor's lost income, which ownership has captured. In a labor-intensive $15 trillion economy, let's say 75% of that income might go to labor and 25% to ownership. Change that to a highly-automated economy, and the numbers might be 40% of $15 trillion go to labor and 60% go to ownership. The economy stays about the same size, but a few owners have pocketed a
LOT of dollars that used to go to labor.