Honestly, income disparity is a poor way to measure fair outcomes in an economy. Supposing the purchasing power per dollar is the same in both scenarios which is a more desireable outcome:
While the households in scenario 1 are all better off than their equlivalents in scenario 2, the focus on more equitable distribution would lead people to choose scenario 2.
We should be discussing how we can grow the economy to ensure that the standard of living of everyone within the economy improves as much as is possible; not discussing how to create an economy where the realitive reward of success is minimized.
I'm not using it to measure outcomes though... I'm using it as a measure of taxation.
It's just like energy. A lot of places with Solar and Wind plants also have coal or nuclear plants for a "Baseline" because the technology hasn't gotten sturdy enough yet to always provide enough "base" energy.
While for coal or Nuclear, you can just crank things up with a knob.
It's irresponsible to raise the tax burdern too high on the rich, because that amount of money fluctuates wildly.
You need a strong baseline taxation. This is why spending needs to be kept low, because obviously you can overtax the dependable "baseline" people who don't make much.
A good start would be selling every military base in a country that we beat in a war over 20 years ago.
I mean, Do we really need bases in Germany and Japan?