I was going to say exactly the same thing.

The lowered scores are the result of a rational strategy in the face of superior competition.

The optimal winning strategy in golf is not necessarily the strategy that will get the best score, on average. A good player might be fully capable of shooting, say, 8 under par, and without Woods in the field, that's what they would do. But if they are faced with needing a 10 under par to win, they have to start taking chances, and (on average) they end up with a worse score then they would have otherwise (7 under par, according to this study).

The players are not idiots. They know this full well. But they are willing to do a little bit worse (on average) in order to have a chance of beating Tiger that one time.

An even starker example of this happens in figure skating competitions when one competitor is capable of landing a high risk jump, like a quadruple axel. It forces all the other competitors to perform the same high risk jump if they are to have any chance of winning. Most of them botch it, so they do worse than they would have otherwise.

But it has nothing to do with a lack of incentive, intimidation, distraction or anything else postulated by this article. It's the result of a rational high-risk strategy, given the circumstances.