We may all end up near enough (for all practical purposes) at the same endpoint if we all worked hard and performed necessary rotations and frame changes given our situations. The brain is very malleable.
There is also the fact that people start at different places for different areas and that chooses where they end up specializing. And there is probably some self-fulfilling prophecy going on that trains people to avoid smarty pants subjects which are vital for developing rigorous thinking. why is it a matter of pride to be terrible at maths and technical subjects? or the fact of growing up with certain teachers and society all but directly informing you that certain races aren't up for certain more mathy subjects. I can certainly attest to that stuff messing up your ability to keep on when things get difficult.
Anyway, your point gets into issues of free will and consciousness that philosophers have been debating for centuries. If everything has a cause, how can we say what we're actually responsible for, and how much is just a reaction to random chance? Perhaps consciousness is largely an illusion: the brain makes decisions based on firmly ingrained circuits that function at a subconscious level, and only later does that bubble up to the conscious level.