This had led to a two party system in the US where both parties are nearly identical, save for some superficial differences, so that any notion of choice is an illusion.
Even if I agree with you that policies undesirable for most of the population are pushed using this "two parties one program trick", we have to admit that is not so simple and that is preferable to a dictatorship.
I think we have to try to improve from here because is undeniable that there is some advance.
In the EUA, maybe you have dynasties that take turns in power, but the idea of some president just refusing to left the white house is inconceivable.
Just compare that with the normal in human history.
I think that removing people from power is the "strong problem" to solve and, democracy, the current imperfect democracy, is a big steep in the right direction.
The real strength is that we can remove the people in power without violence.
If we examine this in the context of human history is a remarkable achievement.