Earlier quoted context omitted.
Don't forget taxes. In that bracket, in California, you're paying 50% of your income in taxes, and so $100K/month is actually $50K/month. I think OP is overselling the point, but not by nearly as much as people think.
That's not how tax brackets work. The effective tax would be about 26%.
* Self-employment taxes: Lower-income people are usually 1099, and are typically subject to additional 7.5% tax
* Sales taxes: Lower income people typically spend most of their dollars on sales-taxable items, so an additional 10%+ on post-tax amounts, which figures out to additional 15%-ish on pre-tax income
* Health insurance: Lower income people typically have to buy their own health insurance, something that should have been provided by the country but isn't, and is effectively a systematic tax on everyone
* Health deductibles: Insurance sold to lower income people doesn't even cover the first few thousand dollars a year, while higher income brackets pay close to zero deductibles. In many other countries "deductibles" isn't even a thing; they too are an effective systematic tax on lower income brackets fueled by the oligarchy of government and financial powers
* Car registration fees: Registration really only requires paperwork done once; recurring annual "registration" is a tax rebranded as a registration
* Property taxes: Even if you don't own, you pay them -- your landlord passes them through to you
The list goes on and on. Taxes are split up like this only because there would be an uprising if they lumped it all together, so they split it up and tax you in pieces and chunks (April 15 is only one chunk) so that you think you're paying less, psychologically.
But yeah, 50% is about the right number for that income.