**Scope of this answer**

*This answer only addresses the particular situation that the OP says provoked her question — the lack of advice (in the form of lack of comments) in downvoting and voting to close a [previous question](https://biology.stackexchange.com/questions/107331/ion-plasmacluster), and the reason given for the close votes.* Her first sentence implies that this is “not nice” and “mean”. As I was one who downvoted the question I will not let this go unchallenged. That is all. *This answer does not address the general question of the friendliness of this site*, nor does it invite comments unless they “ask for clarification or add more information”, are free of personal remarks and confine themselves strictly to this answer.

N.B.<br>
Any criticism in this answer is criticism of the *arguments* of the OP, not of criticism of the OP *herself*. Any use of words such as “reject” and “resent” are used *defensively* against general remarks which could reflect on me personally as a down-voter and close-voter of the question mentioned. In rebutting arguments it is necessary to maintain that they are incorrect, but this should not be taken personally.

**Answer**

The term “Be nice” was at one time part of the *Code of Conduct*, but this has now been *replaced* by a list of what is regarded as [unacceptable behaviour](https://biology.stackexchange.com/conduct):

 - No subtle put-downs or unfriendly language
 - No name-calling or personal attacks
 - No bigotry
 - No harassment

Thus “not being nice” is defined by SE in terms of *unacceptable comments*, and clearly does *not* embrace *refraining from commenting*. 

It would seem that by being “mean” the OP means other than unacceptable behaviour as defined by SE: instead she regards it as a “lack of the kindness” in failing to explain the reasons for downvotes and votes to close. However, as has been pointed out numerous times by list members and moderators, people choose not to provide explanations in comments because of the antagonistic responses they have received by both posters and other list members with their own definitions of  “unfriendly language”. That was my situation and I resent the associated behaviour being described as “mean”.

Two list members were of the opinion that a question regarding whether a technology could [“Harm human body or food”]( https://biology.stackexchange.com/questions/107331/ion-plasmacluster) was a request for  “health (not medical) advice”, an opinion that the OP regards as unreasonable. As this clearly means “if I use it will it harm me?” it seems to me perfectly natural to regard it as a request for health advice. I categorically reject the implication that this choice was “a cover when one can’t close for failure to show research.” It was not.