The way I read it, the parent post does add extra meaning with that word "just", that meaning being "if you don't know how to do X, this is not considered acceptable here", going beyond just the particular problem to the 'meta-level', asserting what the expectations are from people in this role.
That is one way to interpret it, another is “it won’t be hard to do this”. You do not have to leap to the conclusion that something is a personal attack.
