This is a genuinely contested policy question where reasonable people disagree based on different values and empirical judgments. Let me lay out the actual considerations rather than a verdict.
Arguments for higher rates on the wealthy:
•Income/wealth inequality has grown substantially in many countries over recent decades
•Diminishing marginal utility of money suggests a dollar taxed from a billionaire costs less in wellbeing than one from someone lower-income
•Revenue could fund public goods, deficit reduction, or services with broad benefits
•Some argue current systems allow wealthy individuals to pay lower effective rates than middle-income earners through loopholes, capital gains treatment, etc.
Arguments against or for caution:
•Higher rates can affect investment incentives, business formation, or capital flight, though the magnitude of these effects is heavily debated among economists
•Behavioral responses (tax avoidance, restructuring income) can mean higher statutory rates don't translate proportionally to more revenue
•Some argue government spending efficiency matters more than revenue levels
•Definitions matter enormously: taxing wealth vs. income vs. capital gains all have different effects and enforcement challenges
Where the real debates are:
•Economists disagree on the revenue-maximizing top rate (estimates vary widely)
•There's disagreement about whether inequality itself is the problem, or whether absolute living standards/mobility matter more
•Different tax types (wealth tax, higher marginal income rates, closing capital gains loopholes, estate taxes) have very different tradeoffs and are often lumped together in public debate
My honest take: this hinges on value judgments (how much you weigh equality vs. other goals) combined with empirical questions that are genuinely unsettled (behavioral responses to tax changes, optimal tax theory). I don't think there's a factually correct answer here I can just hand you—it depends on what you're optimizing for and which economic models you find credible.
What's driving your question—are you thinking about a specific proposal or policy debate?