Sure, but the argumentation in that blog post is that novelty seeking is a proxy for dopamine sensitivity, and dopamine sensitivity may be linked to extraverted

Sure, but the argumentation in that blog post is that novelty seeking is a proxy for dopamine sensitivity, and dopamine sensitivity may be linked to extraverted/introverted tendencies, hence why that gene study is relevant. But, as I noted, since multiple genes likely regulate for dopamine sensitivity (not to mention things like sleep, diet, etc), there are many factors which regulate those tendencies, and it's false to claim there's a dichotomy and that people are fixed to one tendency or the other.