I never talk about it after a game. It does not belong in church. Some of it is in good fun.
I dealt with it for 20 years in church following BYU wins. I have never brought up a Utah win in church. I like the people too much to hurt them. I know how it feels to lose the big game.
Before a game or during the off-season - some fun teasing is great. I belonged to a ward that held a tailgate party the Friday before the big game. The party was great fun. People came dressed in the colors of their team.