If smack talk is the only thing that motivates an athlete, he shouldn't be in the NFL. There are other things that should motivate a professional athlete and hopefully some of them motivate Sherman.
I've spent my entire professional life around athletes in a wide variety of sports and at a wide variety of levels, and have met some of the players from the great Vikings teams of the 60s and 70s. They had quiet confidence, which came from their Hall of Fame coach, Bud Grant. It seems to me that a little quiet confidence would help calm things down quite a bit.
That said, an interview in the heat of the moment should have been expected to generate the heat that it did. As the saying goes, don't ask a question if you're afraid to learn the answer.
In those days, I did too, the thought was for not give your opposition "bulletin board material" which motivated your opponents. No, we did not want that to happen. Lull them into complacency was the thinking. Haha. Instead, the opposition was "heaped with praise" about how good they were, and all the "bad" thoughts were internalized. The thoughts were really about kicking their asses all over the field, which has not changed from yesteryear.
Today, the culture of the NFL has changed to be '"a little bit more" in your face.