Nobody ever complains about sales tax (which is the quintessential regressive tax) until you get deep in the weeds of policy discussion.
Some sales taxes have been sort of progressive. I don't know the current details but years ago the first $10k on a vehicle purchase was excluded. This was at a time when average/cheaper cars cost under that. Theoretically, that only impacts the wealthy people buying luxury cars. Of course I don't think they ever adjusted it for inflation and they may have even removed that exclusion. But yeah, it's mostly regressive. I do hear people complain about sales tax sometimes.
I think many people agree that the best kind of tax would be on money inflow (income, capital gains) rather than things like property, sales, etc. I think the implementation is the part nobody can agree on.
From a theoretical standpoint the best taxes would be on monopolies that extract economic rent and taxes on externalities. The prime candidates are the land value tax and carbon tax.
Can you expand on that? Does that include capital investment if one meets the loose "materially participated" stipulation?
"The prime candidates are the land value tax and carbon tax."
This doesn't seem like a good idea. A carbon tax is transactional, so it could be avoided. Maybe good for policy implementation but not good for revenue. Land tax seems very similar to property tax already. We are seeing pushes in many states to eliminate it due to the high burden on lower income families and the elderly. For example, you may be taxing them on "wealth" that doesn't exist. This places the government in a position to take assets someone already owns. It's also mostly regressive as property tax is now. If you tax the inflow of money, then you know there is money that can be paid and can even be collected before the person ever receives it.
Well, we do for income tax. It's just that the cut off limit is extremely low ($12k). Based on tax credits, one can even pay $0 in tax and get money back.