The study you mentioned was, even at the time of its publication, quite dubious - finding a negligible correlation (0.23) in amygdalae size in a very non-representative sampling. In a replication attempt that correlation was found to overstate it by more than 3x, finding a correlation of 0.068, which is essentially statistical noise. There's nothing there except clickbait media doing their thing. I'd also add that framing the amygdala as the 'fear center' is itself also quite ridiculous. There also remains the question of identity. I consider myself liberal. I imagine you would object. Who's right? Ah modern 'science', but there I go again challenging that hierarchy.
[1] - https://en.wikipedia.org/wiki/Authoritarianism
[2] - https://en.wikipedia.org/w/index.php?title=Authoritarianism&...