Spending and taxation are tied together. Iowa sales tax is less regressive than many other states. We exempt food, medical care, gasoline, utilities, and even clothing on sales tax holidays. After a low-income family pays rent, insurance, heat, fuel, day care, prescriptions and doctor bills, and car payments, there is not much disposable income left to be taxed. To not fund education fairly is more regressive than sales tax.
Property taxes are regressive as well.
The overall fairness of the system will change very little, if at all. Property taxes are not tied to income and have to be paid by people on fixed incomes and by those with low incomes. Working families benefit from increased activity in the construction trades. The state sales tax is less regressive than the LOSS tax, since the local option tax does not exempt utilities, which has a huge impact on families in poverty. Sales tax is the only viable political option.