Higher wages drive prices up, and price out less productive workers. Sure, the people who remain employed are better off. But what about everyone who has to pay higher prices, and workers who are now unable to find a job?
Why is it ok to tax profitable businesses/people for the sake of equality? I get it if they don't earn their profits fairly. Why should we steal from top producers and redistribute? Taxes should not be a means to redistribute wealth. It should be directly tied to whatever they are funding. More importantly, people should be free to chose what to spend their earnings on. Does the government own the people it governs? Does it have a claim in what people chose to produce? Having income tax forces everyone to pay for things they might not want (like a wall).