Regarding point 3, the older you are, the more people 17 years younger than you are truly grown-ass adults of a reasonable level of maturity and comparable position. I'm old enough to be a grandmother if I got started early, and someone 17 years younger than me, for example, would be 29. While I seriously doubt I would be drawn to someone that young, a person in their early 50s could very reasonably find someone in their mid-30s to be a peer suitable for a romantic connection. I also have a stepbrother who is enough my senior that his oldest child is only eight years younger than me, the same age of my youngest brother, and the idea of him hypothetically dating my mother-in-law is weird but not completely horrifying.