From the information posted here, this seems to be a case where a single
disruptive user, having been expelled from a larger project, is squatting on a smaller project which he has turned into a personal fiefdom. Under these conditions, and where the user in question is the only project admin, it is hardly remarkable that no community movement to desysop has formed. It is unlikely that anyone inclined to stand up to such a user would still be active on the project.
If the information posted here has been largely correct, there is absolutely no reason -- and no excuse -- for not desysopping this user. This strikes me as a profound failure of stewardship.
Cheers,
Sam / Visviva