I am not sure I would include oh-my-zsh as someone's personal zshrc. Moreover I thought OP had made a distinction between bash (10k) and zsh (1k) so I am not sure how o-m-z counts as a bashrc? I will take your word for it but I cant imagine what people put in there bashrc to get to 10k. The entire bash-it repository is 8,588 and over a third of it is bash completions which seems to duplicate the majority of what is already provided by bash-completion. And I am not sure that bash-completion is really "my .bashrc."
edited to reflect distinction between parent and grandparent comment