You can look up economic studies on the marginal utility (satisfaction/benefit) of wealth for an individual, and it’s absolutely the consensus that it declines rapidly the more you have. Take $100,000 from a middle class person, and you have a massive negative impact on their life. Take $100,000 from a billionaire, and the impact is basically nothing. It’s similar with businesses - the more wealth they have, the less marginal utility they get from it. Take $1,000,000 from a small business, you bankrupt it, while it’s nothing but a rounding error for a large enterprise.
If you’re an anarchistic or libertarian, you won’t believe much in taxes at all, that’s fine. But if you believe the government is useful, then the funding/taxes must come from somewhere, and I believe progressive taxation is the best way to do this - the way to raise taxes with the most minimal impact on utility. Virtually all nations do this, for the poor-to-fairly-wealthy individuals and businesses. However, the insanely wealthy individuals and businesses wield their power to change laws, and pay insanely low tax rates, shifting the tax burden onto everyone else. This is the part that I consider unethical - the uber-wealthy and lawmakers teaming up for the benefit of the few at the cost of many.