I suppose this question could be seen as a duplicate of When should comments be flagged as "not constructive"? but my question is specific to particular comments and I don't think I'd get an answer if I posted my question as an answer to When should comments be flagged as "not constructive"? . Hence my making this post.
Anyway, the comments in reference are in response to http://meta.stackexchange.com/a/203301/186308 . They include, among other things, someone saying something like "@HugoDozois /facepalm". I flagged it as not constructive but no action seems to have been taken and I'd like someone to walk me through how exactly it - and some of the other comments there - are constructive.