In short - no.
I have direct experience with this phenomenon, I have stood in the same place that this guy was standing and although I didn't bow out in the same manner he did, I DID stop posting at my game's forum and it was at the ORDER of higher management, because the amount of time I was spending firefighting was deemed to be all out of proportion to the PR value of said firefighting.
Now, some people will claim that if the game is good enough there won't be the NEED for fire fighting in public forums. It's a nice theory - except that by this yardstick there hasn't BEEN a decent game released in the last five years!
Back on track - I have two predictions:
1. That post was cleared via higher management, or the guy involved IS higher management.
2. It will have a zero effect on sales.
Eon