Chess is believed to be a theoretical draw. So top chess engines, which are not too far off from theoretical optimum, tend to reach drawn positions, which are not too exciting.
My understanding is that to combat this, engine tournaments like TCEC force an "interesting" opening on the engines.
What I don't understand is why this should be necessary, when there is a seemingly more natural way to reach the desired effect - which is to use a contempt factor, i.e. a lower score for draws, for both players.
With high enough contempt, both engines will strive for complex, tactical, interesting positions for which neither is sure who will win, but are unlikely to result in a draw.
With the advent of ML-based engines like Alpha Zero and LC Zero, this is even more natural - the contempt can be baked into the training, so the engine doesn't just avoid draws in-game, the learned network treats drawish positions as inferior.
But I've not seen references to contempt being used that way - rather it appears to be a tool to maximize the traditional scoring, when there is reason to believe a difference in level between the engine and its opponent. Its goal is not to make games more interesting for us human observers.
So - am I correct that contempt is not currently an accepted way to make engine games more interesting? And if so, why not?