Second, online daters are a self-selected group, who decided to invest time, energy, effort, and often money (for paid sites) into finding a romantic partner.
That is, there is no evidence that extroverts are best matched with introverts, or people who are open to experience prefer others who are also open to experience.
This offline pool of partners is by definition restrictive.
That is, individuals typically encounter relatively small numbers of potential partners from whom they can choose.
The guy needs to assess the situation, weigh his odds, approach her and if not immediately rebuffed, he needs to impress her, entertain her and spend money on her.
Then after all that, he may find out she wants someone taller, makes more money, etc.