Noam Chomsky characterized this view of democracy as a "system of ratification", rather than true democracy, in his PBS interview with Bill Moyers in 1988. It is true that politics *today* is largely a matter of choices the formulation of which is largely beyond one's control; and it is true that we must work both within the set of available options to select the least harmful, and without to try to transform the system.
But surely this is not what we should strive for in a definition of "politics". Politics should be democratic in the broadest sense, which means you do have a voice in shaping choices, to the extent that they affect you, and that power and privilege have minimal (if any) effect.
Bill