our current tax system is set up so that the people who need the money the most get to keep what little they earn. any kind of flat tax system greatly increases the tax burden on the poor while massively cutting taxes on the rich. it's extremely unhealthy for the economy to have a broke middle class while all the money congeals at the top, its completely unsustainable.
Our current tax system is set up so that the rich pay for everything for everyone while the poor pay for nothing. It doesn't make sense to take more money from people and give them no more, or in some cases, even less benefit. Whether or not you think they earned their money, it's their money. It's not inherently owned by the government, and every dime taken by taxes is money the government gets of someone elses money. Taking huge chunks more money from people but giving them no benefit from that extra money taken is extortion.
taxing someone for 50% of their income when they make $200,000,000 a year leaves them with $100,000,000 a year to live on. taxing someone 0% for making $25,000 a year gives them that tiny amount of money in an economy suffering from rapid inflation to scrape by.
It's not about poverty line vs top 1%. In any and every tax system people are going to get tax breaks if they're below the poverty line, flat tax or not. Here's how the
FairTax system I supported earlier deals with this:
The FairTax provides a progressive program called a prebate. This gives every legal resident household an “advance refund” at the beginning of each month so that purchases made up to the poverty level are tax-free. The prebate prevents an unfair burden on low-income families. Learn more.
Regardless, you skipped past most of my argument. The issue is that we're spending too much money, so taxes
have to be progressive or else the government won't be able to extort enough money from the public to pay for their poorly planned budget. If spending is cut then the government won't need as much money, which would make a flat and fair tax perfectly fine to fund the government without taking an unfair proportion of anybody's money.