Ahh, you're right, I didn't really draw that last line between all this stuff and Thor turning into Odin! But honestly that's because the answer is: it just feels narratively interesting to me that Thor would start turning into a person he's afraid of being as a trauma response. Also most of Thor's model of kingship is from Odin, and if he's struggling to hold the remnants of his people together he's probably going to fall back on what he knows.

Thank you for listening to my character blithering :)