Hmm... perhaps perfectionism also rears its subtle head... when you place a high value on obeying social mores and combine that with some perfectionism... the more complex the social environment the longer before you are ready to enter. Even more complicated for a kid when other kids are following mutable social rules.
A not quite introverted, not ASD situation that may be quite common amongst gifted? Even worse is if you have a high degree of empathy and read frequent disconnects between what is said and done and what is felt.
