How To Close The Income Gap

Education.

But not just any education: education that helps you help others.

A software developer helps businesses work more efficiently.
A marketing consultant helps businesses bring in more customers.
A trader allocates resources to the most efficient companies.
A chef helps people eat healthier.
An investment banker helps businesses preserve cash to keep operations running.
A professional athlete entertains lots of people.
An interior designer helps people live happier.
etc., etc., etc., etc., etc.

A primary difference between high earners and low earners is that high earners have more knowledge on how to provide value to others, resulting in higher pay for providing that value.

Have a freakish competitor who is taking away your customers? Find better ways than the competitor to help your customers.