One should never stop pointing out egregiously bad things. If you stop complaining about something you start accepting it, and eventually it becomes one of those extremely stupid things everyone just takes for granted.
Sounds like some of us would like to change the guidelines to be against twitter reposts to HN. Might not be agreeable to everyone but surely we can agree that should be a valid opinion to voice.
If you'd like that to happen please bring it up with dang. Don't complain about it in the comments. But don't hold your breath, it's not likely to happen.
Perhaps linking to one of the tweet concatenating websites would be a solution. (The ones which are summoned almost immediately in a reply after the freight train of distinct thought snippets leaves the intersection.)