In some situations, you are expecting some kind of judgment or reward for your choices, and can reasonably expect to be penalized for robbing the judges of the ability to judge your choices (because they can’t tell whether you “legitimately” chose the same as someone else, or just copied something.)
I think the most bright-line example of this in your list is “aversion to just straightforwardly agreeing with another intellectual rather than emphasizing differences”—doing so (depending on context) means you are giving no information about the quality of your own opinions (assuming you got to hear the other person’s opinion first), so you lose out on any reward you might have expected for having good opinions. Copying xkcd’s style also falls in this category, I think, except that gets even closer to the proscribed category of “plagiarism”—where you’re not only not clearly deserving of the reward for what you produce (since it’s not clear whether it’s original or copied), but you’re arguably hiding that fact, and will be penalized accordingly.
The same thing can be true in a subtler way in other cases. For example, “not discussing topics once they are too commonly discussed, even if they are not resolved”, “using a turn of phrase that has been used many times before”—these are still cases where I think people are judging you on originality, even if that shouldn’t the primary factor they’re judging you on.
(Some of the other examples I think are very different: all the ones about personal style I think have more to do with an aversion to asymmetric relationships. If someone is copying how I look or act, that gives me the feeling that they’re devoting a lot more brain-space to me than I am to them, which I think creates a very instinctual “creepy” vibe.)
In some situations, you are expecting some kind of judgment or reward for your choices, and can reasonably expect to be penalized for robbing the judges of the ability to judge your choices (because they can’t tell whether you “legitimately” chose the same as someone else, or just copied something.)
I think the most bright-line example of this in your list is “aversion to just straightforwardly agreeing with another intellectual rather than emphasizing differences”—doing so (depending on context) means you are giving no information about the quality of your own opinions (assuming you got to hear the other person’s opinion first), so you lose out on any reward you might have expected for having good opinions. Copying xkcd’s style also falls in this category, I think, except that gets even closer to the proscribed category of “plagiarism”—where you’re not only not clearly deserving of the reward for what you produce (since it’s not clear whether it’s original or copied), but you’re arguably hiding that fact, and will be penalized accordingly.
The same thing can be true in a subtler way in other cases. For example, “not discussing topics once they are too commonly discussed, even if they are not resolved”, “using a turn of phrase that has been used many times before”—these are still cases where I think people are judging you on originality, even if that shouldn’t the primary factor they’re judging you on.
(Some of the other examples I think are very different: all the ones about personal style I think have more to do with an aversion to asymmetric relationships. If someone is copying how I look or act, that gives me the feeling that they’re devoting a lot more brain-space to me than I am to them, which I think creates a very instinctual “creepy” vibe.)