square neck

When using the term "square" in that context, you're emphasizing not just the rigidity or uptightness of the person, but also implying a lack of intelligence or narrow-mindedness. It's a way of criticizing someone for being closed-minded or foolish in their thinking or actions. In this usage, "square neck" would indeed be a disparaging remark implying that the person's mentality is constrained and unintelligent.

In a Conversation Among Friends:
Friend 1: "I don't understand why anyone would want to try something new. Stick with what you know, right?"
Friend 2: "Wow, what a square neck thing to say. You're really limiting yourself."

In a Workplace Setting:
Colleague 1: "We've always done it this way, and it's worked fine. There's no need to change anything."
Colleague 2: "That's such a square neck approach. We should be open to new ideas and improvements."

In a Social Media Comment Thread:
Commenter 1: "People who listen to anything other than classic rock just don't appreciate real music."
Commenter 2: "Seriously? That's the most square neck comment I've seen all day. Musical taste is subjective, dude."

Person A: "Can you believe John thinks he's so smart just because he reads a few books? What a pretentious jerk."
Person B (interrupting): "Hey, ease up. Calling someone out for trying to educate themselves is a bit square neck, don't you think? Let's encourage learning, not tear it down."

Person A: "You're just a brainwashed fool for believing in politician X's policies. Can't you see how misguided and stupid you are?"
Person B (intervening): "Hold on a second. Attacking someone's beliefs like that is beyond square neck. Just because you disagree with person's politics doesn't mean you should insult their intelligence. Let's keep this discussion civil."