Finland was a very good team but not on the level of USSR. USA beat Finland and won the Gold Medal but it technically wasn’t the Gold Medal Game because of the rules of the round-robin tourney. If Finland beat the USA, there was a way Finland didn’t win the Gold Medal. In fact, Finland that year received no medals (gold, silver or bronze).
Sweden finished third and won the bronze medal. It's interesting that they were the only opponent the U.S. did not defeat in that tournament. They played to a tie in the first game of the preliminary round when the U.S. pulled their goalie and scored with less than a minute left in the game.
Sweden finished the medal round with a loss and two ties, and Finland had two losses and a tie. If Finland had beaten the U.S. they would have had a win, a loss and a tie. I think the only way they would have been out of the medal race in that scenario would have been if Sweden had beaten the Soviets in the last game of the tournament by a wide margin (they ended up losing 9-2 instead). If Finland and Sweden had both won their final games, then three of the teams would have had identical 1-1-1 records and the medals would have been awarded based on tiebreakers.