> what boils down to shaming people for not communicating the way you want is wrong
Which is exactly what the second half of your post is, but moreso than the person you are criticizing.
There is no point in having a discussion board if people are going to be criticized because something they said with sincerity might offend somebody. That is the nature of speech.
The second half of his post is not a critique of how the point to which he responds was communicated, but of the point itself. He's saying that the message "people shouldn't write like that" is problematic and flawed, not that it itself shouldn't have been written like it was.
As to your second point, that any speech at all might offend someone so there's no point in drawing attention to that fact, on the contrary, the commenter is actually making a very concrete point. He is talking about a very specific thing, that this prescriptivism about writing style alienates and turns away a lot of people that could otherwise make valuable contributions. It's not a general statement that any statement might offend somebody, but a highly targeted examination of the consequences of such speech policing.
Which is exactly what the second half of your post is, but moreso than the person you are criticizing.
There is no point in having a discussion board if people are going to be criticized because something they said with sincerity might offend somebody. That is the nature of speech.