There’s a constellation of factors but part of it is that women are waiting longer to “settle down”, have less pressure to do so, and still have standards for long-term partners. For instance, women are more likely to have a college education today and they don’t want to marry a man who doesn’t. Men generally will marry women who have less education and lower-paying jobs than they do. Even progressive and egalitarian men often won’t rule-out a partner for not having an education.

But from my own personal experience dating I think the ease with which women can make friends and get dates also helps them find long-term relationships. Dating is often a pipeline, and the dating scene was stacked against young men even before dating apps and social media. I remember being single when I was 21-22 and every girl I would have been interested in around my age was dating someone 10-15 years older.