Of course it could have been written more diplomatically. Yet, many people clearly don't find it to be offensive/inappropriate - especially when viewed in the context of the entire post, which was very well written and diplomatic.

Moreover, I can very much see how those precise words could be said verbally, in person, in a completely disarming, effective manner - by using particular pacing, tone, gestures, a wink, etc. Whether Linus would do that is another matter - but your comment was talking about how it would be inappropriate anywhere.