I think you get wealth disparities as a result of specialization. Should a surgeon make the same as a ditch digger? They’re both important to society but almost anyone can dig ditches. Not everyone can learn to be a surgeon, and the requirements are strict otherwise people won’t trust surgeons not to kill them, which is a net negative for society if people don’t trust them. As a result it’s a small group of people who can do it, and it takes decades of dedication just to get to “I am a surgeon” levels.

Voila. Wealth disparity.

A healthy amount is fine and normal. We’re at cartoonish levels where even bare mention of the word “wealth disparity” causes anaphylaxis in some people.