That's just not true. The top 1% pay 33% of the tax (and the top 10%, "upper middle class", pay 70%). I think myth just causes confusion and misplaced anger.
Yes, but these stats obviously take into account only paid taxes and wealth that remains visible. If you have 50 bn$, of which 1 is kept and taxed locally, and 49 moved through shell companies to offshore tax heavens, you'll still end up as one of the top tax payers, even if you are evading about ~5000%. Obviously this is much harder to do if you earn 200k/year.
Yes, if the top 1% paid their fair share, they would pay more than 33% of the country's taxes. But nevertheless they do in fact pay 33% of the country's taxes.
Would you have someone who's broke and unemployed pay the same amount of tax as a billionaire?
Ideally taxes shouldn't be a large burden to anyone. The richer someone is, the larger absolute amount of taxes that person can pay for the same burden level. In fact, it's not just a fixed percent. The richer someone is, the larger percent of taxes that person can pay for the same burden level.
The rich got to where they are by using the infrastructure built by the government. A rich person gets more value from the government than a poor person, so thus it's fair that a rich person pays more in taxes.