The whole point of Spock was that, due to the difficulties of being an interspecies child, he had chosen to live in the Vulcan way. To be more Vulcan THAN Vulcan, in fact. TOS made it clear that Vulcans were not emotionless robots, but that they considered displays of emotion to be in bad taste. It was all about control and order, and Spock was especially sensitive about that, due to his childhood bullying and also because he perhaps was trying to overcompensate in order to earn his father’s love, since he probably felt badly about their disagreement over his career path.
Also, the character of Spock—one of the greatest characters in all of pop culture—is an excellent study of how to handle loneliness and inner conflict with bravery, dignity, and intelligence. Kirk, to a lesser extent, also exemplifies this, since many episodes emphasized the personal costs and loneliness of being a commander. But both men rose above all of those hang-ups and became their best selves.