Going a bit more doylist here, when Vulcans are well written they project their own insecurities on other species and that scares them. They then do all kinds of rationalization to deal with their feelings. In one of the season 4 episodes of Enterprise there’s a small scene that covers this a bit.
It’s mentioned a few times that Vulcans feel strong emotions but suppress them because they are afraid of losing control.
That’s a good point. However, is it fair of them to then look down on other species that don’t suppress their emotions?
Going a bit more doylist here, when Vulcans are well written they project their own insecurities on other species and that scares them. They then do all kinds of rationalization to deal with their feelings. In one of the season 4 episodes of Enterprise there’s a small scene that covers this a bit.