Dems/Liberals saying they will raise tax RATES on the “rich” allows them a more immediate visual for their voter base because it’s a number they can put in big bold characters on national TV and print for them to see and implies they have solved the problem of the “rich” not paying their fair share. Closing loop holes does increase the amount of taxable income but is a changing number annually dependent upon the income earned by the 1%-5% where as if you raise the tax rate % that stays the same, whether the “rich” are earning more or less $ annually through paychecks, capital gains, and other investments, etc.