Because the distribution of wages is so skewed to those who make the salaries decisions, the rich need to be taxed at a higher amount and even a higher rate. And they have been but they need to be made more progressive yet, imo.
The fact that the inequality has increased dramatically over the last 35 years means that the tax rates should reflect that change by increasing the rate for the top brackets - it has not, in fact that top rate has dropped.
“Fair" is subjective but the fairness can be judged by looking at the changes in our tax rates with time in response to the changes in inequality shown above. And the fact that many/most of the rich manage to avoid paying their designated (what some people term “fair”) tax amounts (by offshoring or paying capital gains instead of regular tax rates) shows more unfairness.
Hope this answers your “question”.
Informed by Data.
Driven by the SPIRIT and JESUS’s Example.
Promoting the Kingdom of GOD on Earth.