Who can edit the Help Center?
I'd like to suggest some changes. My notion is to propose the changes here in Chemistry Meta then have the changes made in the help center if there is a consensus to do so.
i.e. myself (as of the time of writing), can edit a grand total of two Help Centre pages, namely:
Stack Exchange, the company
The rest of the Help Centre cannot be touched by us, and can only be changed by employees of Stack Exchange, presumably the Community Managers (CMs). Jon Ericson, a former CM has written about this: Improved Help Center - site-specific pages and site-specific edits to all pages.
In this post, Jon left open the possibility of getting a CM to edit the Help Centre (after community discussion), although I'm not sure if anybody in the five years since has tried to do it. For what it's worth, this subsequent post: Can we mark some more Help Center articles as moderator-editable? didn't quite get anywhere.
I think it is more hassle than it is worth to contact the CMs with proposed changes. These would (for good reason) probably have to go through a lot of vetting, and is more bureaucratic than I would like.
Furthermore, I'm personally skeptical of how many people read the Help Centre in great detail (see Jon's post above, too). It's frequently the case where those who need to read it don't read it, and those who read it don't need to read it.
If we want to create more guidance, an easier process seems to be to write this on Meta, tag it with faq, and then add a link to it at the top of the Help Centre (where we can edit).