That won't be as easy as you think. Again, how would you do that if monetary incentives are mostly gone? If nobody is poor enough to help with evil plans, evil plans become really hard.

Heck, add in another simple rule: make all wealth information public. If nobody is poor and nobody really rich, there won't be much incentives to abuse that information and if we know peoples worth, it will be glaringly obvious that somebody is cheating

I know that this is an obvious oversimplification bit small changes like these areuch easier to implement than say "let's all become anarchist and the world will be fine!' because that will never happen.

These small changes keep everything else the same and at least it solves a huge list of problems from people dying from hunger to most crime to most wars to climate change. All of these mentioned are mostly only possible because we allow extreme wealth.

Take extreme wealth away and the world would be so much better

That was a wealth tax, not a tax on income. So, nobody would be worth more than 10 million, and earning 10 million is almost out of the question. That means you can't own a huge business by yourself, to start with.

I might argue that if any single individual is in the position to collect $10M+/year, the economic system is already dysfunctional. That individual is operating as a gatekeeper rather than a value center and the position they occupy needs to be broken up and reorganized.