Heavy topspin works best when it's used by a match smart player, not by a strong dummy who just pummels the ball hard up the middle.
Heavy top allows for increased short angles, running the opponent well past the doubles sidelines. It's also effective for dipping teasing passing shots, to make the netperson volley upwards.
Great for driving tentative players off the baseline, so your short angle works even better.
But no, a dummy hitting hard topspin is not the best player on the courts.