I believe the point is that if you want a romantic relationship with a woman, cultivating a friendship with her in the hopes that romance will develop is almost always a bad idea. Occasionally such romance sparks "out of the blue", but more likely nothing will ever happen, and it is a huge investment of time and emotion that basically never pays off. So if you aren't interested in the woman for the sake of friendship alone, it is better to just forget about her and move on.

If you find a person interesting and worth being friends with, by all means don't reject such an opportunity just because the person is a woman. That's idiotic. It's just a terrible dating strategy, that's all.