That one question already has resulted in 150+ deleted comments between the question and several answers, many of which are quite offensive. The majority of the rest of the deleted ones are not constructive and/or off-topic.
There are have been multiple different discussions ongoing on various posts there which belong in either chat or on this meta site, not on the posts.
In addition to the large number of off-topic comments, there are nearly forty flags on various components of that question of all manner -- nearly all valid.
There are also multiple answers there which do not try to provide a constructive solution to the OP's problem.
Everything there is now locked.
Response to comments/updates
Should it be unlocked? There are currently three meta posts which relate to that post - two of which are unresolved, one of which has been investigated by multiple SE employees (I don't know if any have read this one). At this point, given the prolific rate of flags generated by that post, the blatantly offensive comments completely violating the SE be nice policy (see this post for a full list of the deleted comments), and minimal value in unlocking the post I am unsure it will ever be unlocked.
Users - a plethora of users - continued to post offensive, off topic, and meta discussions after multiple moderator comments and explanations. This is why most of the posts there are locked as:
This post has been locked due to the high amount of off-topic comments generated. For extended discussions, please use chat.
Is it wrong to delete comments?
Stack Exchange isn't a discussion board. It's a question/answer site. See the section on comments for the role of comments. This is the policy we as moderators are following when deleting comments.
If you do not believe this is how comments should be used, I encourage you to ask a question on the main Stack Exchange meta site to generate support for SE changing their policy on how comments work.
Was treatment of the answer biased?
The question I raise is about process, and giving an answer and its author fair treatment under rules I have agreed to that allow me to continue contributing to this and other StackExchange sites.
I am going to write at length about the actions taken on this specific answer, so you can better understand the actions taken and why.
The answer in question here, while overall somewhat popular (controversial - its received the fourth most downvotes of any answer remaining on The Workplace), does not actually answer the question. The asker asks, "how can I not shake hands with people in the workplace, because of my religious beliefs?" and this answer says, "you have to either shake hands or quit your job."
This is not helpful to anyone looking at this question and is among other reasons why that post is controversial.
See how to answer, specifically:
Read the question carefully. What, specifically, is the question asking for? Make sure your answer provides that – or a viable alternative. The answer can be “don’t do that”, but it should also include “try this instead”. Any answer that gets the asker going in the right direction is helpful, but do try to mention any limitations, assumptions or simplifications in your answer. Brevity is acceptable, but fuller explanations are better.
After considerable comments and discussion, (including input from Monica via comments) that answer finally got an actual "answer" on the fifth revision. I use the phrase "answer" generously here, because rather than attempt to help the asker, the poster gives two possibilities and then explains how people will find it discriminatory - without trying to even provide any advice to the asker in how to address these issues.
As a side note, this is also interesting to me in that it effectively takes information directly from the other two answers at the time. In other contexts it's quite clear the author does not believe you should use any content first posted by others - however their answer blatantly copies content from two other answers there as their "alternative" - from posts which were in fact present and viewed by the author.
Presenting possibilities as "answers" and then proceeding to only explain reasons they are going to fail - with literally no attempt made to help the asker avoid these pitfalls - is not helpful. A constructive answer would help the asker overcome the pitfalls and be incredibly valuable.
Then, after all this, there were revisions made that expanded upon the already present theme in the answer that "to work you need to give up your religious beliefs - or quit." This was articulated in the edit to remove it. Note that the answer picked up flags after the edits were rolled back, which means the language there is still offensive to others reading the question.
The question is "how can I politely decline a handshake [due to religious reasons]?" It is not, "please provide commentary on whether or not I should follow my religion and what do you think about this?" Monica locked the answer when the author persisted in editing this commentary into their answer for the reason: "This post has been locked while disputes about its content are being resolved."
Some good reading would be from the be nice section of the help center:
Bigotry of any kind. Language likely to offend or alienate individuals or groups based on race, gender, sexual orientation, religion, etc. will not be tolerated. At all.
Honestly, I'm surprised someone from the SE staff has not come by and deleted that answer outright given how strongly and intentionally it violates the above policy. The site moderators have been exceedingly generous in allowing the language in that answer to stand in spite of the clear policy on "Be Nice" as applies to bigotry based on religion. If anything our attempts (primarily from the other moderators, since I removed myself nearly entirely from moderation on that question given I had an answer there) to remain impartial have made us allow inappropriate content longer than otherwise would be fair.
Some questions are hard to answer. That's fine. But the proper response to hard questions isn't an inflammatory post which basically says "... then find work elsewhere. This is how we like doing things in the US of A."
Hopefully this helps you better understand the why actions were taken on this answer the way they were.