No one is getting rich on 2% a year.
You're absolutely wrong.
How so?
OK. You're a billionaire. You put a billion dollars into a Bank of America savings account. They give you an interest rate of 2% per year. You close the account after 1 year with an extra $20,000,000 interest.
You now are rich on 2% a year.
$20,000,000 IS rich. Even next to 1 billion. Its not a matter of relativity. Its already been scientifically demonstrated that money stops buying happiness at about $70k a year; everything after that is just people attempting to make up for their personal shortcomings.
I submit if you had a billion $'s to put into the bank, you were rich already. So, while 2% of that is a huge amount to someone that is poor, it is nothing to someone that has a billion $'s.
So, your example is flawed. People don't get rich by getting interest from a bank, they get rich by being highly productive and adding huge value to the economy. (I'm not counting people that fell out of a rich crotch or won the lottery. This is why I favor the 0% tax rate btw).