I suspect that I am the moderator that you are referring to, and I am happy to try and address any issues that you (or anyone) may have with my moderating style on this focussed Q&A site. GIS SE is not a forum and so the principles that I try to apply to it when moderating are those of a focussed Q&A site rather than those of a discussion forum.
Thank you for posting a link to an example of the concerns that you raise. I'll explain the action that I took there as an example of why I think it was appropriate, before going on to your generic concerns.
When I first saw Mode (Statistics) on mapping yesterday, it had been posted 6 hours earlier by a user who has been on the site for over 3 years and was simply:
I have a city map with digital boundaries. Each polygon has some
numbers between 1 to 7. For example one of the polygon has
4,4,6,1,4,7,3,4,5,4,2(The mode is 4 for this polygon). I wonder is
there any possibilities in Arcmap to find mode for each polygon and
I considered it unclear and voted for it to go On Hold. I believe this was in line with the first comment by a very experienced user there an hour earlier:
How are these numbers stored? As a single text field or as 12 numeric
fields of as 12 polygons each with a single number?
When I came back to it 3-4 hours later the asker had included a link to an image hosting site and the same potential answerer had commented:
I too cannot view the image it just takes you to a website full of
crap/adverts. Edit your question and upload the image directly into
stack exchange. It is unclear what you are describing. Are you saying
that for example a polygon has 25 points intersecting it and these
points have ID numbers ranging from 1 to 7 and it is the mode of these
you want to extract?
The asker was offering to try and move their image to yet another external image hosting site so to me the question had not yet been improved sufficiently. I voted to leave it closed (for now) and made a comment of:
Please don't use a different website just use the Picture button that
I think my actions above were fine. If I had not placed that question on hold, then I am not sure that the user would have tried to make it clearer, and it might still be unanswered. It may have received an answer anyway, but I review many thousands of questions each year, and to me it had the hallmarks of one that would only add to the workload being placed on our volunteers, which is described at Improving on 19,000 unanswered questions?
If a question does not meet the site's quality standards, and it is evident that it is going to take additional volunteered efforts to assist it to do so, then I am a firm believer that we should always vote to close immediately because the sooner it is fixed, the sooner it can attract quality answers, and we do not know how long the asker will be watching their question to provide any requested clarifications.
You have made a request:
What I would also like to request is that the same user not delete
their comments to the OP after the on hold is released. It removes a
critical layer of transparency, and one that holds the moderator as
accountable for their behavior as they have held the OP.
If you ever see me delete a comment for what you believe to be an inappropriate reason then I am happy to have the post flagged so that I, or one of the other moderators, who I often ask for peer review, can review that course of action, and undelete them, if appropriate.
However, in the instance(s) that you cite, it sounds like the comment deletions are following SE guidelines in How do comments work?:
When should comments be deleted?
Comments are temporary "Post-It" notes left on a question or
answer. You should not expect them to be around forever: Once a
clarification has been made, an edit added to the post to include new
information, or the issue in the comment is otherwise resolved, it is
subject to deletion. In reality, many obsolete or chatty comments
remain untouched due to the high volume of comments posted, but this
does not mean that they can't or shouldn't be deleted in the future.
An overarching theme to your question seems to be whether I should vote to place questions on hold significantly less often. It is certainly something that I grapple with, and at times I go through phases where I do vote to place questions on hold significantly less often.
However, I keep being confronted with Improving on 19,000 unanswered questions? and I think "stitch in time" actions by moderators (who have been empowered to act instantly) are a necessary part of the strategy for avoiding unclear questions remaining open and attracting unclear answers. Unclear questions consume volunteer resources as they try to encourage askers to fix their questions, and prevent those potential answerers from actually answering questions to help build a repository of high quality focused Q&A instead.