We detached this comment from https://news.ycombinator.com/item?id=37315195 so as not to take discussion off topic.

New accounts are subject to additional restrictions because of past abuse by spammers and trolls. Obviously that comment was legit, but as we don't have software smart enough to distinguish legit comments from bad one, some human intervention is often required to rescue the legit ones. You did this yourself by vouching for the comment, which unkilled it.