It is easy for the attractive to say that; like most traits, people don't like to believe dumb luck helped them. It makes a much better personal narrative if it was their own hard work. That doesn't mean it's backed up by any fact.
Yeah. Attractive people are fairly consistently approached or hit on or treated differently or what have you every day in real life. Remove the approach anxiety that the other 90% who DON'T approach these people but want to by creating an easy forum for approach, and you have an overwhelming amount of messaging. I don't blame girls for being quickly disillusioned. Even as a guy, I feel like the pickings are slim, and I'd much rather date a friend than meet someone through OkC.