Steward
A steward is someone who actually practices w:stewardship, e.g. product stewardship. It is not someone who simply takes control and then uses that control to express their own view.
The claim that the sysop power structure of Wikipedia is represented fairly by Wikimedia is probably true. The claim that this representes the users is probably not. See alleged Wikimedia corruption for more on this.
Much propaganda by the usurpers who created the Wikimedia Foundation focuses on this claim that they are somehow anointed stewards of the GFDL corpus. There is no basis for making this claim in the GFDL. Indeed members of the Wikimedia Board of Trustees mostly cannot even read the corpus, and engage in harassment against some GFDL corpus access providers. See sysop power structure and sysop vandalism and Wikipedia violates GFDL for more on these specific breaches of stewardship.