As far as I know, it is possible to transfer the ownership of a question or an answer to the community user. For example, this was done for answers in some of the sandboxes here on meta (as I've learned from some comments posted there).1
The effect of this is that the original poster is no longer an owner of the post and they do not receive related notifications (about comments, answers, edits...) Of course, they are no longer awarded badges related to the question. (This is different from making post community wiki - in such case the original author still gets notifications.2)
We have here several threads which by design are expected to get many answers. (For example, reopen request threads, tag management threads. Maybe some other posts in the future might get into the same category.)
I can imagine that in such situations the poster of the question might prefer not to get notifications about all new answers. (But the decision should be made by the OP. Maybe somebody might prefer to get such notifications - if they are interested enough in tag management, or closing and reopening and they want follow all new developments in that post.) I do not have examples where something like this would be a reasonable request for a post on the main site - but maybe there are such situations, too.
From some comments on other posts I see that this has to be done by a member of Stack Exchange staff (unless I misunderstood something).
Question. If I want to have ownership of some post removed (so that I no longer get the notifications), what is the right way to request this?
Should I contact our local mods via flag or possibly chat. (And they will check whether it is a reasonable request and then ask some Stack Exchange employee to do this?)
Or is it better to contact directly Stack Exchange (maybe using "contact us" link)?
If both possibilities are acceptable, which of them is preferred?
TL;DR: If I want to be disassociated from the post, who should I contact?
In Mad Scientist's answer to an older post they recommended writing an email to email@example.com. However, the question was different from what I am asking here. So it probably still makes sense to ask about this, even if there is a possibility that all I get will be a confirmation of this answer. (But maybe I will learn from the answer that other ways to do this are possible, and in some cases they might even be more suitable.)
The recommendation to use the "contact us" link is also given in this Meta Stack Exchange post: How do I remove my name from a post, in accordance with CC BY-SA 3.0?
1 More specifically, if I look at Sandbox for drafts of long, complex posts, there is this comment by Grace Note: "At the suggestion of the moderators, I have gone and changed the associated owners of all the answers here to the Community user. This way, the original owners will not receive excess pings for each time another user uses the draft space for their work. Enjoy!"
2To expand on the main differences a in more detail: If a post is made community wiki it lowers the reputation needed to edit the post from 2000 reputation points to 100 reputation points. The poster no longer gets reputation for the votes on the post. But the author or the post still gets all usual notifications (if a post is edited, if there is a new comment, if an answer is posted). The post is still displayed in the OP's profile and the OP still gets badges from it.
If the post ownership is removed, the post behaves as a post made by another user. (I.e., no notifications, no badges, not shown in the profile.) Some details about this can be also found in this Meta Stack Exchange post: How do I remove my name from a post, in accordance with CC BY-SA 3.0?