it's part of being polite and gracious. It is a sign of gratitude and class that they emphasize the positive. I ding them a little for using clichéd phrases, but I can appreciate that they are trying to move on without being mean or rubbing it in the faces of their old team/fans. At the end of the day, there is nothing they can say that lessens the blow *that much*. It sucks to get dumped. No two ways about it, but it is a kindness to attempt to phrase it nicely.