Bruce is a very good coach that gets the best out of his players and wins a lot of games, while being very real in front of a microphone.
Yes, he hasn't had post season success, but looking at the teams he's coached, were any picked to be cup champs in the first place? Joel Quenneville had pretty much the exact same playoff reputation before the Hawks... got a cup capable roster, saw post season success. Go future how that works for a good coach. (Q isn't near as likable though, by a long shot)
I have no doubt, if Bruce had a real contender of a roster, you'd see real success in the post season.