progressive tax bracket system is wdiely used all over the world, while flat 1 is rare. there's a reason for that. higher income, higher tax, it's that simple.

what li really complains is loopholes on those non-salary incomes. then fix them! but what does it have to do with progressive income tax? they are 2 different issues.

his logic is like:

an overweight guy, who eats normal lunch and heavy dinner, wants to lose weight, so decides to scale down both meals.