What is the value of being King of the Ghetto? At what point is enough excess enough? At that point, the rest should go back into the community.
I now live in a country on the higher end of the taxation rankings. While I don't enjoy giving up 40% of my income, I do enjoy a lot of benefits (good public transport being the most useful perk for me) that I simply didn't have in the US.
However, I am not going to blame the US entirely for its rising rent problem. Yes a lot of it has been due to the excessive pay of dot.com and other Wall Street windfalls (since when people can afford something they want, they ultimately don't care what the price is... which drives prices up rapidly). However, another major factor is the enormous influx of foreign property purchases. Chinese nationals now own a huge percentage of the properties in the city center. Rental rates are going up at an incredible clip. Unfortunately, rent controls are only a little successful (because people take advantage of that system, just like people do many things to avoid paying taxes).
I really don't see any solution for now. Even providing a living income to all members of society won't prevent some regions having rental rates well beyond what "normal" people can afford. However, try to imagine SF or Manhattan with no low-wage workers. There would be no restaurants, no road repair crews, no public transport drivers, etc. etc. Who would pick up your trash?