Assuming employers still have the authority to choose their workers, it seems like this strongly incentivizes them to push out older employees and bring in younger ones. This is especially true given that competence does not seem to be a factor in how much people are paid. Any company would rather pay less for a more qualified employee than pay more for a less qualified employee.
Meanwhile, workers will probably object to the fact that after age 50, their net income actually starts going down (assuming we are also implementing the tax rate portion of your experiment, this is where the increased tax rate overcomes the increase in gross income). Employers will probably object to this as well on the grounds that it basically amounts to an indirect tax on them (since the entirety of every salary increase after age 50—plus a little more—goes straight to the tax collectors).