Most every modern flat that proposal has details to not fuck you over if you are poor. Take my man Ben Carson's tax plan. He was for a no-deductions, no-loophole flat 14.9 percent tax that takes income only once, with no double up for capital gains, no AMT, and no pointless itemization for everyone above 150 percent poverty level.
Seems fair to me.

It's like self parody at this point.