the evolution of human society as one that was basically manipulated to operate based on fear and scarcity mindset

This makes sense, since that kind of mindset was in place long before humanity. Nature and life are all about scarcity, and the fear of missing out. Gobble up your values as soon as you can, because you never know if they'll still be around to be gobbled tomorrow.

Since that is inherent in life as we know it, it's pretty easy to see why it would be a large part of human society without any mastermind pulling the strings to make it so.

That being said, I agree that it's important to recognize these feelings when and if they are unjustified in a particular situation. And it is also important to recognize that such feelings are used to manipulate people all the time. (Personally, I consider all communication to be a form of manipulation.)

all the while we can't see that we're actually doing this for beliefs that were never our own

This is a strange statement. How can you have a belief that is not your own? In one sense, all of your beliefs come from some exterior place: whether it's societal dogma, or perception of physical reality (except, perhaps, the cogito). Even so, a belief, by its definition, is always yours. The real question is whether or not that belief correlates with reality or not.

Overall though, I think this idea of a cage is a question of perception. Ultimately, yes, there is no such thing as free will, and all of your choices are determined by a chain of causes that stretches back trillions of years. Recognizing feelings of fear and scarcity will never change that. But at the same time, you will never know all of those causes - your knowledge and understanding will always be finite, and therefore choice will always be necessary. In other words, the cage is only there when you cross your eyes a bit. :)

I go into a little more detail about that in a recent post if you want to take a look: The Determined Will