It was because one of the Dutch players in an Olympic beach volleyball match was a convicted rapist, who attacked a minor in England many years ago. (It's never been completely clear to me how this guy was allowed to compete in the first place, but after serving his sentence he returned to his native country and is carrying on with his life.)

When the women from Radio-Canada discovered they would have to call a game he was playing in, they decided to remain silent and the entire match went out over TV without them saying a word.

Canadian broadcasters refused to call Olympic volleyball match involving child rapist