I'm dating a younger male right now, and "general unsuitability to healthy relationships" really rings true to an extent. His friends are more or less constantly bragging about how they "link up" with their friend's partners (without the friend knowing/consenting), lead people on, and so on. It's obviously not all younger people. I think that the rise of social media has affected this area of human interaction more than other areas, perhaps. The concepts of boundaries and respect are shifting. I think what is considered a "healthy relationship" is likely undergoing a significant shift. Maybe in a generation or two the "healthy relationships" will all be polyamorous ones, and monogamy will be considered the strange/unhealthy kind.