Disqus should be added to the .com site. That’s all there is to it. There’s no amount of convincing you can do to me that tells me otherwise (and no, I don’t think security is a good excuse). I believe Disqus functions a lot better than what WordPress offers, no offense to WordPress workers themselves or whatnot. I would just feel a ton better with Disqus. Installing WordPress is far too complicated for my tastes (and very time-consuming), so I would like it if there was an option to import or use Disqus via the .com site.
Disqus can only be used on WordPress.org installs and we have not seen any announcements of changes being made. I flagged this thread so it will moved moved to the Ideas Forum where we make suggestions to Staff.