Man, this topic is getting good!
The way I see it, there are a couple of issues, centering around changes in the cultural norms.
1) The perception of a "good" man/woman is has changed. Integrity & character have taken a back seat to bravado & income. Men & women dress in flashy manners to attract attention to their bodies and to show they have money. Dating conversations have become about cash and sex instead of personality and values.
2) Women & men are waiting later in life to establish serious relationships. In an effort to "establish" themselves (school, degrees, career), people put off the serious effort required to nurture healthy relationships. IMO, many of us pick up "fast food" relationships because they don't require as much work and when they go bad, we can walk away with little guilt and an easy scapegoat (the other person). Additionally, because younger folk tend to want the flashy date, many of the stable, non-flashy people become jaded. By the time the folk attracted to flash realize they NEED substance in a relationship (there are more people like this than we are willing to admit), the people that would fit their needs are now turned off & discouraged.