Inherent factors could explain different ratios of conservativ vs liberal views in men vs women of that age group, but not drastic changes to such a gap. I'd also rule out brain development as a factor simply based on differences between countries. Human populations do have variances, but not to such a degree when it concerns something this fundamental.

This may have affected my younger brain's susceptibility to extremist views

Or for a positive spin "openness to new or different ideas and values"