I’m not talking about 18-21 year old women now, I’m talking about those who got married when extramarital sex was taboo. The best place I’ve seen to hear about how they chose their spouse is a radio site called StoryCorps.

People (especially young people) make those decisions based on impulse and emotion, then rationalize after the fact. You can't believe the explanations they give. Most people just say what they think they're supposed to say, or what they think would please the interviewer.

One piece of concrete data is that a huge fraction of people in US cities 100 years ago married people who lived in their same block, and a substantial fraction in their same apartment building. That’s evidence of a different approach to mating.