But then libertarians like to change things too, but in very different ways to what you'd approve of if you identify as left/progressive. So it's not that simp

But then libertarians like to change things too, but in very different ways to what you'd approve of if you identify as left/progressive. So it's not that simple. There will always be a spectrum of opinion and values, and people will always try and simplify it down to a "left" and a "right" wing, and it won't work very well but people will insist on doing it anyway. For what it's worth I don't believe it's genetically hard-coded; it's as much adaptive to culture and responsive to what people see happening in their own lives and in the world around them.