$108k in NY and San Fran does not make one rich. One year I actually made over $108k - I am lucky if I can find a home to buy that has 3 bedrooms, 2 bath, 1700 square feet in decent shape and within a safe community within an hour commute to Boston that we can afford in a down economy where house prices are low. I know because I am going through this right now.
I don't consider that to be rich or even upper middle class. And Boston is cheaper than NY or San Fran.
And I've also said that it should be a flat tax all around including cap gains, interest and income with no deductions. That would close loop holes and be fair all around.